Here are some tips from Adam Sapp, Director of Admissions at Pomona College.

Keep a short accounting of how you are spending your time. This is a moment where everything counts. Keep a reading list of the books you read for fun. List extra time spent babysitting siblings unexpectedly. Did you work hard to call grandma a bit more? Jot that down. Make a resume of summer programs admitted to or summer events you planned to attend that were cancelled due to Covid. Draft some reflections on how you developed ways to cope and manage during this difficult time. I don’t know if you’ll use ALL of this; I can’t promise that, but I do think this fall that colleges may find creative ways to ask students about this stay-at-home time on the application. If and when they do, your students will be glad they have some previously created documents to refer to for accuracy and to help them reflect. 

This is a great article by Julie Lythcott-Haims former Admissions Dean at Stanford University.  I disagree with her suggestion for Plan B, 2a. If seniors take a gap year and take college classes at the local community college, they will lose the financial aid they got as a first year student. Check with your specific college. Most financial aid goes to first years. If they apply as a transfer student, it is highly likely that they will get much less financial aid. For some colleges, especially highly-selective institutions, it's much more competitive to apply as a transfer student.
Link here.

Here's Julie's take:
To Go or Not To Go: That is the Question
How to talk about starting college amid COVID-19
Julie Lythcott-Haims
April 25, 2020
You’re not alone in stressing about this: The college decision is a big deal in any year. But in a year of pandemic, where data is imperfect and no one really knows when life will return to “normal,” it makes for a lot of confusion, bewilderment, and anxiety. If you’re feeling any of these things, please know that you’re not alone, your feelings are valid, and I’m here to help.
 
There are actually two separate topics to ponder: “Which admission offer does your kid want to accept?” And “What do they want to do if their college is only open virtually in the fall?” I think the questions have to be answered in that order; choose a school regardless of COVID-19 and with that decision made you can move on to the second conversation about contingency planning in light of COVID-19.
 
Before analyzing the second topic, step back and look at what the colleges are facing this fall. They may:

1. open the entire campus as normal;
2. open with classes held virtually (no residential life or campus experience to speak of); or
3. shut down entirely (it is more important than ever to understand the financial circumstances of the school your kid might attend, i.e. get online and read the tea leaves - you do not want your kid to go to a school that might not survive the economic hit of COVID-19.) 

As a family you’ll want to be familiar with all three of these possibilities. Obviously Plan A is what we all hope will happen – life as normal would sure feel good right now! On the other end of the spectrum is Plan C – a disaster we hope befalls no school. The one to pay attention to, therefore, is Plan B because there’s a really good chance that it will happen.
 
So, what does the student want to do if it’s Plan B? Reasonable responses include:
 
B1. Great, sign me up, virtual learning is fine with me and it won’t be like this forever!
If this is your kid’s response, and you agree that you want to pay those dollars for that experience, great, go for it. The schools will be thrilled to have your kid because they need those tuition dollars to help them through this difficult time. So, go ahead and put down your deposit (check the deadline – many schools are pushing it to June 1 to give you more time to decide) and feel confident that no matter what, your kid is starting college this fall. (This is the second-most expensive option—Tuition but no room + board. But note, the schools know that families are questioning whether it’s fair to be charged full tuition for a distance learning experience, and literally as I write this, schools are figuring out whether they can afford to discount tuition accordingly. UC Berkeley announced on 4/23 that it will NOT discount tuition, for example. So, monitor the schools you’re looking at – this issue of full/discounted tuition should be settled relatively soon.)
 
B2. Hey this isn’t what I worked my tail off for, I want the full college experience (or hey I’m not paying full tuition for online learning)! 
What we’re talking about here is the desire to put off going to college until the institution can welcome you literally with open arms, otherwise known as “deferring.” The colleges are afraid to allow this – if not enough students enroll, the college may have trouble staying afloat. (Some may not allow deferrals, or may limit the number of deferrals granted, for this reason.) But at the end of the day, it’s your money and your life. It’s perfectly valid to feel this way, and if you do, I think you have two options (the philosophy behind both of which is you don’t want to sit around and do nothing for a year because that will definitely set you back):

1. Take some virtual classes at your local community college until your college is fully up and running again. Community colleges typically have fantastic instructors. And many of your credits may transfer over to your four-year school (you’ll need to check that) so this is time and dollars really well spent. You can live at home or create a new germ circle with housemates in town to gain independence and practice those adulting skills. Note, it is normal practice in any given year for colleges to require that you not be a full-time degree-seeking student anywhere else while holding a spot with them, but taking a few classes somewhere does not violate this policy. (This is the third-most expensive option—community college tuition and perhaps rent/groceries if you’re not living at home.)
   
   
2. Create a structured gap year for yourself where you pick 3-5 things you want to learn from September-May and you access all the online learning and in-home learning available to you. You could choose to study absolutely anything – go deeper into what you’re truly passionate about, learn a new language, learn to cook ten fantastic meals, read the great literary works of the past century, take up a musical instrument, focus on a myriad of science topics, engage in home and car repair, hone your woodworking skills and other crafts, study any topic of history imaginable, get good at gardening, and beyond. Study.com and Khan Academy and other sources of online learning will take you far, as will the opportunities you can avail yourself of in your own house. (This is the cheapest option—No tuition, but maybe some fees here and there for something you’re studying online.)
   
   
3. There’s a new idea being floated that I’m excited about, in which young people get paid to do the work needed during this crazy time. It’s called Corona Corps, and it’s gap year meets Peace Corps meets GI Bill. You can read up on it here.

Note, if the school doesn’t allow you to defer, that’s not the end of the world. If this is the right choice for you, decline your offer and apply again next year with confidence that if you’ve undertaken something meaningful during this gap year (whether at a community college or self-designed) it will only strengthen your application.
 
B3. Wait, what? I’m starting college but still living with my parents? I need to get out of here!
For the really mature high school senior, getting on with adult life may be the primary imperative. If this describes your kid, you might explore the idea of them renting a place near the college with housemates who attend the same school, so they can get to know and care about the local community while taking classes online. If this option is chosen, the student will effectively be joining a new germ circle with their housemates. i.e. If we as a society are still “sheltering in place” they will not be allowed to go back and forth between their new place and their childhood home (aka your house). So, this is a commitment! But for the right student, it’s an exciting opportunity to continue growing, maturing, and building skills despite the pandemic. If this is your situation, put down your deposit by the deadline (again, check to see if that date has changed) and in a few months start looking at places to rent in the town in which the college is located. (This is the most expensive option—Potentially full tuition (unless they discount it) plus the cost of off campus housing, groceries etc. Although, note, off-campus housing is usually cheaper than on-campus housing except in cities with a very high cost of living.)

B4. It’s too soon for me to decide. I need to wait and see what happens.
This is valid. If this is what your kid is feeling, they can put down a deposit at the place they honestly will most likely attend. The deposit holds their spot, and they will not get the deposit back if they decide not to enroll after all. Please note, it’s unethical to put down a deposit if you know you probably won’t go there – so don’t let your kid be that person!
 
Final thoughts:

1. There is no “off track” ever, and particularly now.
2. There is no “right choice” here - everyone has imperfect data and everyone is winging it.
3. You will not make a “wrong decision” – after carefully evaluating your options, and what matters most to you, make the decision that is right for you and your family, and commit to it.
4. Be kind to yourself. This is hard. But we are all going to get through it together.