A little late, but here are my 2 cents.

I'm a teacher via the TFA way (I hate TFA, btw), and when I was first interviewing a couple years ago, my director told me something that to this day sticks out: don't spend more time planning a lesson than it will take to execute.

My first year was miserable (for reasons I won't get into), and I found I was burning out rather quickly. I would go home and want to do nothing but sleep. You're still getting adjusted to the work you do, and it can take a toll on you. I had an extremely rough first semester as a teacher, and when I came back from winter break, I came back with a "fuck-it" mentality. Believe it or not, I threw everything my TFA "support" (should not be called that) had "taught" me. I became more of myself in the classroom and would spend a very small amount of time planning lessons. My school is a rough school (charter where we get the kids who are borderline expulsion from the school district), both behaviorally and academically. My mentality, though I feel bad now, was something along the lines of: whether I spend hours planning a lesson or 30 minutes on it, it will go equally as bad tomorrow, so I'll pick my battles and spend the minimal amount of time. Things got better slowly after a few weeks, and by the 6 week period or so (if I remember correctly), I began spending more and more time planning lessons, creating activities, etc.

If there is one thing I learned from doing that--and I may be going on a tangent with what you're asking--is that you need to simply be yourself in the classroom, and come to the conclusion that you will not be able to get to every last assignment to grade, etc. Once that gets through to you, trust me, you will pick your own battles. I essentially stopped collecting homework and would walk around checking work as students worked on the warm up. You either had it, or you didn't. It's only worth about 10% of the grade (if that) anyway.

For exit slips, I tried something like this that worked in order for me to survive my first year. I teach math, so this was easier for me, but depending on what you teach, you can tweak it around a bit. I try to teach a different objective every day, or at least 3-4 a week. My exit slips are 1-2 questions long. As students walk out, I will briefly check to see students have mastered the objective. If they're getting it spot on, I say "have a nice day," give them back their slip of paper, and off they go. If I see they struggled with something, made a mistake, etc, I will keep it and grade it, and then use that to remediate during after school "tutoring" or the next day. It's on-the-go grading, and if you were marked present and I gave you back your exit slip, you will get full credit for that. otherwise, I grade it accordingly. So I went from collecting 125 pieces of paper of homework and 125 exit slips to essentially collecting 0 homework and a few dozen exit slips--which is much more reasonable. I don't feel bogged down by the amount of grading I need to do.

At the end of the day, you just need to set aside some time. Get a planner that lists days by the hour. Block out the time you're at school working, and then see what time you have left. Block out the time you have to sleep, and see what's left now. For me, it's about the 4:00 pm to 10:00 pm slot. Nowadays, I don't allow myself to spend over 1.5 hrs nightly (usually much, much less) on anything related to work. As teachers, we can end up with insane amounts of paperwork by week's end, but just realize that at the end of the day (or week), you simply won't be able to get to every last sheet of paper, and pick what's most important--especially if you teach >100 students.