There is a peculiar passivity that rental culture encourages, and it is worth naming before we get into anything practical. The passivity goes like this: this is not my home, it is someone else's investment that I am paying for the use of, and therefore the decisions I make about it are not really decisions - they are stopgap measures pending the real decisions I will make when I own something.
This is a way of living that defers the present to a future that may not arrive in the form expected, or that arrives very late, or that arrives and turns out to require different decisions than anticipated. It is also, more immediately, a way of making yourself feel like a guest in your own life, which is a miserable state to sustain for five or ten or fifteen years.
What you can actually do
Most rental agreements prohibit or restrict: drilling into walls, making structural changes, repainting without permission, fitting new fixtures. Most rental agreements say nothing about: what furniture you buy, how you arrange it, what you put on surfaces, the quality of your bedding, the art you rest against the wall rather than hanging from it, the plants you keep, the books you own, the objects you choose to live with.
The list of what is permitted is much longer than the list of what is not. The problem is that the things that are not permitted tend to feel like the things that matter most - you want to paint that horrible magnolia, you want to hang the mirror properly. But the prohibition on drilling is not a prohibition on making a home. It is a constraint, and constraints, as we keep discovering, are workable.
The portable investment
The most useful reframe I have found for renting is to think about investments in terms of portability. A good lamp that you love and that moves with you is a better investment than a built-in shelf that you leave behind. A proper rug that transforms the feel of a room and rolls up when you leave is better than wall-to-wall carpet you paid someone to lay. Art that leans or is pinned rather than nailed can go anywhere.
This is not a counsel of cheapness. Some of the most worthwhile things to spend money on as a renter are things that will last twenty years and move house with you five times. A quality sofa. A good mattress. A rug large enough to actually work. Bedding that feels considered. Lighting - proper, deliberate, warm lighting - that can be taken apart and reassembled.
The permission you need
I have rented for fifteen years in New York. I have had six different apartments. In five of them, I painted - not every wall, but one wall in each that needed it more than the others. I asked permission each time. I offered to repaint to the original before leaving. I was told yes each time, partly because I asked politely and partly because most landlords are not actually that attached to the specific shade of off-white they chose in 2008.
The permission you assume you don't have is often the permission you haven't asked for. This is not a guarantee - some landlords are inflexible, some tenancies are straightforwardly prohibitive. But the assumption that you know the answer without asking is its own form of passivity, and it is worth questioning.