What to do as a mid laner when ahead

Hi, So I'm in bronze and I main mid lane. I play the laming phase really good and I am pretty ahead for 80% of my games. But I have a pretty bad win rate and lose games where I'm ahead. The thing is and it's mainly my mistake that I don't know what to do when I'm ahead in mid lane. Do I just sit midlane and push waves and keep killing the enemy midlaner. Do I rotate to teamfights all the time since in iron and bronze people tend to fight every 2 minuites. Do I go to another lane and push there? I always end up going to help my team in team fights and lose cs and then the enemy top laner or someone else that's fed ends up destroying us. What like major tip would u be able to give. I main orianna and lissandra mid lane by the way.