Beyond the Self-Study script there’s the Item Inspector that keeps track of your leeches. I can highly recommend it as a study tool. Let’s you quiz yourself on part of the leeches as well. 
I also like the Shin Wanikani leech trainer as it helps with interference training - when you confuse similar looking kanji for example.
I’m feeling lazi, so just linking to my study log as it’s got all three scripts in the OP post
Just generally speaking, taking time to regularly do leech training is what got me through WK. It doesn’t have to be weekly, though that’s probably good to do, but every other week or when you’ve acquired around 60-ish leeches or so. Then, I’d use the leech trainer and/or self-study quiz and Item inspector to work my way through them.
Most leeches just need that extra amount of repetition to stick, so spending some time on them should allow you to guru, master and enlighten them.
Just hang in there! ^^
