Terminology that I will use:
yarn - this can apply to all from wool to acrylic.
Working yarn - the yarn that you will use, as you knit.
Hold the end of the yarn in your hand.
Whatever hand you are using make sure your ball of yarn is on your working side/the side where it doesn't move across your work so it gets tangled.
Place the yarn between your thumb and your second finger, so that the yarn is over your first finger.
Wrap the yarn around the finger (not too tight, you don't want to cut off your circulation) So that it crosses over your first finger.
Holding onto the cross that you have made, pull the yarn from the front of your finger, underneath the circle you have made, and pull it through.
Holding the yarn that you have pulled through, you let go of the hoop, hold onto the end and pull the hoop at the top.
There you have done a slip stitch, you can use this to start your knitting or your crochet.
