I have a bottle fetish. I look, I see art...lol. I spotted a really neat shaped bottle in the super market on the olive oil shelf, MIIIIIIIIIIIIINE... I had to have it. So I bought it, used the oil, peeled off the stickers and sent it through the dishwasher.
I wanted an attractive dish soap dispenser sitting by my kitchen sink so I brought home a bottle of green and a bottle of blue dish soap and filled my new bottle half full of each color. It's really interesting how they blend yet stay somewhat separated for days and it looks really pretty. I stuck a sticker on the side of flowers just for fun.
You can use different colors and see what you get but it is always a pleasure to look at and a fun way to use your soap. Success!