From someone who can’t do less at work, or break things into projects that can be finished up all neatly and tidily (it sucks) - here’s a bit of advice.
Take the last 5 or 10 minutes of each work day and get a pad of paper. Write down all of the projects you’re currently working on, and some outline notes of what needs to be done on them.
For example, here’s an edited version of mine from last evening:
Wed AM: Beginning of week stuff - routine. nw (no worries)
Wed AM: Beginning of month stuff - don’t forget new calendar! remember to file apps! nw
Wed ASAP! - Create order for last quarter - problems because it’s late? in trouble? check with supervisor. look into marking timeslots for this on calendar in future - lw (little worried)
It does seem like it matters that I have steps to complete listed instead of just the items themselves. It’s not a To Do List, it’s more of a … these things are coming up, and I don’t have to stress, because I know what I’m going to do about them already.
Basically, what I’m doing is really thinking about what I’ve still got going on, what I need to do to complete it, and confirming that I know my way forward, and that I’m (even though I’m not finished) still in control of the work, and that everything is on track.
I’m using that writing as a time to file work projects away as “continuing processes” rather than “unfinished work” if that makes sense. It helps me finish the workday and leave all that there and not think about it at home, and to not stress about it while sleeping either.
It’s not perfect, especially when it’s been a rough patch at work, school, or home, but it really does help.
On a totally different front, I’ve posted before about lucid dreaming, and it really can help. Lucid dreaming isn’t always the best method for handling stress dreams, because most people (myself included) tend to make the dream simply go away, or morph into something else entirely. If you really want them to go away, you need to actually deal with them, in the dream or in life - but if all you need is a good night’s sleep, and you’re pretty sure you know where the stress is coming from, I figure it’s better than nothing!