what's the best way to train modeling?

hey guys,

Curious what you have found to be the best way to train yourself how to build financial models.

I have BIWS and WS Prep, but not sure actually what's the most effective way to self-train.

I was never good at financial modeling in business school, and subsequently I left IBD too early and went into PE too early, and my inability to model fluently has always been a source of insecurity.

I can build simple 1-page models ok, but I'm nowhere near an IBD quant-jock.

Suggestions on how to use these tools best and most efficiently?

I'm NOT asking which modeling package is best, since I already have a few.

I just want advice on how to best study.