how do i get my round cakes perfectly round on the sides
Are you using the wilton pans that have a slight flare to them? If so, invest in some good Magic Line pans (some also like the Fat Daddio pans, but I've only used Magic Line).
In the meantime, when I have to use my flared pans ..... freeze the cakes. While still frozen, stand them up on the side (like a wheel). Use a sharp paring knife and trim the flare off.
Do this a couple of times and you'll realize that buying new pans is worth it!