It can make hard to make a space truly feel like it’s yours. To make it feel like it’s a good reflection of yourself and a comfortable space to be in, where you just feel content by your surroundings, whether it is your bedroom or an apartment.
My biggest suggestion is this: personalize, personalize, personalize.
Is there a series of movies or books you like? Don’t shy away from putting up a poster or two (or more). I know sometimes it seems immature, but if it is something you enjoy, why not be able to see it every time you walk into whichever room you’ve placed it in?
Do you like flowers? Turtles? Cats? Put up artwork or photos of them. If you’re an artist, make your own artwork of them, or if you’re a photographer (professional or hobbyist) take some photos yourself. Otherwise, there are lots of places to get such artwork, or you may even consider commissioning an artist online (there are lots of them on Tumblr, Instagram, and other platforms) who do on request artwork at reasonable prices.
I personally need a night light because I can’t sleep in really dark places and I’m too tense. If you use one too, why not change it up by using a different colored bulb, either by painting one, or getting one from some Christmas lights? I use red, because it does look nice and I like the color, but it also works well for nighttime vision. I do recommend avoiding blue, but any other color should be fine.
Consider organizing your bookshelves by genre. This’ll make your interests stand out more to guests, and you can organize them for yourself when you’re in the mood for a certain kind of book but don’t know which one you want to read. Add shells, figures, edgings, etc. to make them even more personalized.
Your space should be a reflection of you. It can be super minimalist or have a lot of decorations, because regardless of your preference, it still says this is my space.