Iris already shared one sort of method for casting spells that’s worth looking at.
I also really like Sarall’s layout, too!
I am not Wiccan and don’t cast circles, call quarters, or do any of that stuff. My spellwriting and ritual process is a bit different. I wrote a post about it a while back, actually. You may find it helpful!
I also have this older video on my YouTube channel that talks about how to write your own spells.
I definitely recommend going through the Spellcasting 101 course here on Spells8. It might help answer some of your questions and give you a boost of confidence!