check out scurb and scrapcomputer on youtube, they have some videos that could help you (helped me for sure, i now enjoy a jungle round whenever i play SR [ARAM main] and i find snowballing my team is generally easy with ganking junglers
)
other than that, pretty much what DacT1 said
and don't forget, after a successful gank you can tax a few minions for a quick gold injection (burning an enemies summoner spell is always a good gank, take a minion or two quickly and move on)
if somebody shows appreciation for ganking and they are doing good, return to gank this lane often as your laner will be in a great mood and be in a great mindset (and have gold) to make big plays
also the enemy laner will likely tilt which will then turn that lane into a free lane for your laner, now you only have 2 lanes to worry about :)
most junglers prioritize ganking bot and mid lanes it seems however i enjoy helping my top out early, then mid in mid game and by late game the adc should be farmed up anyways to bring the damage but i keep a constant watch down there for two big reasons
dragon is down there and thats important
bot lane has TWO people you can kill :)