Please tell me how to apply mascara well.

They say that to prevent mascara from smudging, it is important to first control oil well.

Mine keeps spreading and clumping.

My mascara keeps smudging, so please tell me how to prevent it. I'm really worried because it seems to droop down like dark circles after a while, possibly due to the oil around my eyes.

I'm curious if waterproof products are good, and I'd also like recommendations for products that don't smudge easily.

I would like to know how to use an eyelash curler and if using a fixer together is helpful. Please also explain in detail if there are any easy methods for beginners.

I find mascara the hardest part of makeup.

Why doesn't it go up properly, and why does it droop and spread so quickly? ㅠㅠ