I'm trying to get more storage on my iphone so I deleted all of my messages

My storage part of my settings it says I still have 1.14 GB of usage even though i have no messages. How can i make this number lower and what are other ways to get more storage on an iphone?

Look at photos, videos and apps. I l transfer all videos to my PC as well as heaps of photo. Apps you don't use much or ever, delete! Hope it helped