To be a millionaire before 40

I am a small business owner, who is very much interested in investing in my future. My goal is to have at least $1 million in my bank account before I turn 40. I have a some dollars invested in bitcoin and SNP 500. For those who have accomplished this goal, given that I am only five years away before turning 40, how aggressive do I need to invest? Any other tips?

Update/edit: since not everyone saw my replies in the thread. I have a little more than 100k invested in BTC and mutual fund. About 80% of that is in BTC. This is in addition to my retirement accounts which are close to 100k and maturing at a good pace, and my real estate equity, which is close to $80k as of now.