If you find creating a schedule for meditating difficult and you tell yourself that you will do it at the end of the day, only to decide in the end that you are too tired to do it and will do it tomorrow, just do a short session in the morning or the middle of the day, don't wait.
A short session throughout the day is better than no session at all.
It's very easy to give in to the temptation of not doing it, even though it's a pretty simple task of just sitting for a few minutes, we can still find every excuse to not do it, and sometimes we just don't feel like doing it, even though we really want to and need it.
Instead, the moment you remember or think about it, go do it, even if it's just a few minutes. Of course, if it's possible, if not then try to do it as soon as you can rather than saying that you will do it later or before bed, because, you know you will probably have a reason not to do it.
Even short sessions can be great, and they can encourage us to go for longer next time, or to find more time for it throughout the day, leading to multiple sessions, and just more time meditating.