One of my hot buttons is when an internet commando/expert will comment on something and give advice that means zero because they don't tell you how to accomplish that feat. The moronic "don't go to the ground" (um, it may not be your idea where the fight goes so....), the "I will just get my gun out and shoot someone who is trying to wrestle me" are some of the most worn out ones, but a big one is "just get up" when you find yourself on the ground may be the single worst and most offensive.
It may well be a great idea, but how can we pull it off against an attacker who is adrenalized, has the initiative, is in the middle of violent action against us, and has already put us in a position we don't want to be in? That is hard and requires more thought than an insipid "just do it".
There are a number of ways to stand up, and here is a short video on one that I have found to be among the best. Why the best? Because it is easily learned, does not require a ton of attributes to pull off, and can be done even against a bigger, stronger, tougher, and faster opponent. I have been teaching this one for a really long time and have found very, very few people who cannot do it after a tiny bit of practice.