How to stop homemade press on nails from becoming bulky?

Hello! I don’t often post on reddit but I felt this may be a good place to ask. When I made my press on nails i always find them to be bulky or that they look odd once worn but not when i’m creating them. Is it really as simple as filing down the edges or is there a technique they made them less bulky on the sides? I would also like to hear general opinion if they are too bulky looking or if i’m just in my own head about it! thank you.