IWTL how to WRITE SMUT

Currently, I'm trying to stop consuming regular pornography because I'm trying to restore my attention span, become more romantic, and generally have a better, more creative outlet for my lust and sexual thoughts.

So, I bought a black locking journal and decided while buying it that I'm gonna set myself a limit. I can only masturbate to things I have actively written for myself.

The problem is I have zero idea how to write good smut. I don't know what to focus on or how to make it, I'm worried letting it flow just makes me look or sound stupid.

I'm just trying to avoid shit like "Her mammaries breasted boobily" or "His weener wanged cockishly."