I have not got a decorative ability how do I learn how to decorate a bathroom
Hello Missie! I would take a look at LOTS of pictures and ideas online to find things you'd like to see in your bathroom. Paint colors, flooring, window treatments, etc. You could make a bathroom board of all your ideas and then come up with a plan for what you can do! Here's something to get you inspired!
To keep it from feeling small, I would focus on keeping all the finishes- walls, ceilings, floors, vanity - not too contrasting.
For a color pallet- what finishes are you going to keep? Tile? Then that’s the basis of your color scheme.
If you’ve a piece of wall art or expensive towels you want to tie in, then bring those with you when you go to the paint store.
Paint is cheap and bathroom paint should be semi-gloss or gloss latex enamel. It needs to not absorb high humidity.
You can decorate by theme or color. For example my good friend in TN loves the ocean and decorated her bathroom with a "sea" theme with starfish on the wall, crabs, and sea shells she collected from the ocean in clear vase. But my other friend painted her bathroom with purple, white, and teal prints. She also used a shutter to hang her towels etc in the bathroom. Just use what YOU love. My grandma had an all pink bathroom, so did my mom, but mine has a western theme. If you know what you love, or if you have collected items from vacations etc use those items. Also consider things such as miniature soaps you make in a white dish, or air plants that only need the humidity to survive, etc. Here is the purple one I mentioned: https://www.hometalk.com/36047306/bathroom-paint-and-li-l-creative-update-under-30
Choose a nice Colorful Shower Curtain, use light color from it to paint your Walls .get matching waste Basket , rug and towels in one of the other Colors in the shower Curtain/or Window Curtain.