How to decorate a 550 s. foot apt ?

I would keep it pretty simple, with some pops of color. And try to make everything as multi purpose as possible - for example, coffee table that has storage.

Yes, don't over crowd it. Smaller sofa with perhaps a chair. If you can't find a small enough sofa, you could also use a loveseat. Tv mounted on wall will add extra room, but if you can't put on the wall, then get a stand that also has storage you can use.

Keep your furniture small in scale, and I would go with a light monochromatic color scheme to keep it open looking. If this is a studio, I would go with a murphy bed. Apartment Therapy has great ideas for small spaces.... https://www.apartmenttherapy.com/categories/small_spaces

I would go with furniture pieces that can double as storage, such as upholstered cubes for end tables, and an upholstered longer piece for a coffee table that can be used to store linens, clothing, shoes, etc. If you have lots of books or collectibles,

I love the Ikea Kallax shelving system, and you can put fabric or basket cubes on them to hide some items..... this is frequently featured on small apartment designs to divide off a bedroom area in a studio, it comes in 4 colors.... https://www.ikea.com/us/en/catalog/products/70301537/

Murphy bed..... https://www.youtube.com/watch?v=7nOZvUPZqGU get your home depot guy to cut to the plans

What have you got to work with? Let's start with that. Here are some links for inspiration!

https://www.onekingslane.com/live-love-home/small-spaces-makeover-the-studio-at-one-kings-lane/

http://www.home-designing.com/2014/04/design-inspiration-for-small-apartments-less-than-600-square-feet

https://youtu.be/J89vsjbEyts

https://youtu.be/X7Q4ou0mPXY

And I would try to get as many pieces of furniture on rollers as possible, like a coffee table, side tables, a bed, the fridge. Anything heavy. This will help with cleaning in a tight place, and give you flexibility when you need to move things around when you have company. And put your bed on lifters so you have more storage.

Use lots of shiny surfaces like mirrors, pictures under glass, and metallics. If you have any windows, try to play them up. Use under cabinets lights to add more interest and depth. ☺️

Pinterest is a great site for getting AWESOME ideas,for do-it-yourself easy things.I took a bed headboard and used it -to decorate.The headboard,I put it against the wall, slide the bed to the wall,and it holds it into position.It looks awesome!

Since I don't know or have a pic of your place maybe this will help:

https://www.homedit.com/small-apartment-decorating/

Carefully I would say. Determine what functions you need. Like office area, sleeping, cooking, sitting, tv, etc. go from there. If you have high ceilings, you could raise the sleeping area under the office. or maybe 2 twin beds in a corner bed could do double duty as a couch with a bolster pillow behind that could serve as storage of linens, off season clothes. If you can look at storage beds with drawers, or get thin box that slide under beds to store things. A dual height coffee table could also be a dining area. use the walls for lighting, sconces, limit tables and lamps. Use all the walls in th kitchen area. Also look at your kitchen stuff. If you don’t use it regularly, put in storage, keep a few boxes at a relative or friends. Use rugs to differentiate areas. Consider a wall of shelves, floor to ceiling, that could House a desk area, tv, books, baskets to hide clother shoes. Go floor to ceiling, use brackets to hold onto wall. IKEA make bookshelves that you could mix and match and screw onto the wall for safety. Also, consider limiting colors. go with few colors and sprinkle them around, like pillows, painting the back of the bookshelves. Think cozy and homey. Good luck