A small room becomes difficult when each furniture decision is made separately. Treat the whole room as one system instead.
Map the fixed features
Record doors, windows, radiators, outlets and anything that cannot move.
Place the largest object first
In a bedroom, that is usually the bed. Test its position before adding secondary furniture.
Protect the walking path
Keep the route from the door to the bed and storage as uncomplicated as possible.
Find unused volume
Look under the bed, above furniture, behind doors and on walls before expanding the footprint.
Add furniture only when it solves two jobs
In very small rooms, multifunctional pieces can be more useful than several single-purpose pieces.