If you don't have a hand held sprayer on your shower, get someone to switch out your showerhead for you - it makes a world of difference in terms of being able to effectively shower while using the shower chair.
When I was non-weight bearing, it was for hip surgery and I used a walker rather than a knee scooter and attached a basket to the front so I could transport small items around my home. Maybe you can right something like that for the knee scooter?
I also found it was easiest to get one of those big water containers with the spigot to have on a table next to the sofa where I spent most of my time, so that I could always have water nearby and not have to get up to get it every time.
https://www.target.com/p/arrowhead-b...E&gclsrc=aw.ds
Esp at the beginning where you might need to take pain pills overnight, keep some pretzels (and water of course) next to you bed, so that you don't have to take anything on an empty stomach.