I'm sure it's been asked, but how do you apply your polish. You have beautifully clean lines. Also how long do you generally wait between applying layers?
Keep your layers thin. I usually paint one layer on one full hand, then one layer on the other full hand, then back to the first hand for subsequent layers. That’s usually enough dry time.
To keep your lines clean, take your time. Once the first layer is down, you will have an easier time following the paint already laid. Cleanup is also a major player in the lines. I clean up around my cuticles using a small angled brush dipped in 100% acetone.
I have a DIY manicure page on my blog here that might help too.