Imagine the melodies you are playing are opera arias. How would a tenor or a soprano sing them? Sing your music in your head like a great singer would sing on stage with great power, energy, confidence and musicality . Then try to copy this with your instrument with the same character. Don't be afraid to make a big show! You can try anything you want when you're alone in your practice room. It'll probably make you miss a few notes in the beginning but it'll greatly improve your musicality and tone and once you get used to it, you'll miss fewer notes. If you practice this way, you'll be able to perform this way and you'll have lots of fun playing!
I am associate principal horn of the Singapore Symphony Orchestra and the author of the progressive methods. I'm happy to share my experience as a horn player and teacher with you.