I've taught a number of people how to crochet. One time I prepared printed instructions, which I ended up having to ditch because no one was using them, but all the other times I just sat next to the person and let them watch my hands and watched them when they were having a go themselves. Maybe bring yarn and needles if the other person doesn't have any, or if they wouldn't know how to get yarn and needles that went together gauge-wise, but other than that I think you just need to trust yourself.