Advice on sizing up and jewelry

Hey so I'm currently at 2g or 4g right now im really not sure, but I got my "Stretching" kit from hot topic a while ago and originally stretched all the way up to the size im at right now gradually with tapers (yikes ik I've been told LOL) but if any of you could give me good brands with actually good stretching kits and any further advice I'd love to hear it!!