Try this until you get a little more experience under your belt.
Always keep a copy of any spell you do. Even if you donâ€™t write a spell that is made of words on paper write down how you do the spell. Every detail, time, place, tools used, words you thought, what type of energy you projected, how you projected itâ€¦ every detail. Thatâ€™s important.
Then if something goes wrong take these notes that youâ€™ve made and work another spell to undo any damage youâ€™ve done. Write a spell that basically says something like (and Iâ€™m just winging it here so youâ€™ll probably come up with better wording but):
That which should not have been done I now undo.
My need is great, my wish is true.
Each thing that is here shown
I cast away and no more is it known
No energy shall remain
By this undoing I gain
And put right that which is wrong
For in my magic right is more strong
Sorry, not exactly my best spell ever, but like I said I was winging it and did it really fast lol. But it should at least give you an idea on how to undo a spell.
Anyway, work things so that you put the above spell (or one to accomplish the same thing) with the notes on the spell you want to undo and just put all the energy you can into the undoing.