meet right below your ear. the side straps may be easier to adjust if you take the helmet off your head. roll the little rubber band as close to the side straps as possible to prevent slipping.
buckle the chin strap. tighten the chin strap until it is snug. no more than one finger should be able to fit under the strap. take a look at the first image at the top of the post to see how this should look.
does the helmet fit right? open your mouth really wide! the helmet should pull down on the head. if it does not, then refer to step 4 and re-adjust the chin 