Well ventilated area , out of your first trimester , follow time limits for the color staying in . And do a strand test because it can take to your hair different with the hormones
I just do mine like a week before due date so that my hair looks awesome in everyones pics
I did mine in the second. It depends on who you talk to but all I was told is that it doesn't matter at all as long as you're in a well ventilated area where you're not inhaling the fumes.
I wait til the third trimester to do mine
They say just wait until after the first trimester because of the fumes. Ive done mine and its perfectly ok.