Irregularity.

Hello, I am a 17 year old female who has EXTREMELY irregular periods... I'm talking about months upon months of gaps between my cycles. I was wondering if anyone had any tips in order to get it going? I've been to the doctor before and he said it's not a big issue until I'm 18 (coming this June). I had one last month and it lasted about 5 days but so far my body is showing no signs of coming this month.. please shoot some tips my way. It would be greatly appreciated.💗