Here's what I do:
Try this recipe and tips: https://www.craftylittlegnome.com/permanently-kill-grass-weeds/
Straight vinegar will do the trick.
Here is a video tutorial for you: https://www.youtube.com/watch?v=2zCS-rfT3Xk
The struggle is real, isn't it?!? This is the most effective all-natural weed killer DIY that we use. It's even been featured on Hometalk! Hope this helps! Hugs, Holly