I just came back to Runescape after 2 years. I have some nice stats such as 71 WC, 63 MIN, etc.

Well I used to be a member for like a month but even coming back to this game I don't want to be a member anymore.

So what's the best way to make money in Free Worlds?

Best way is Rune rocks but your 61 mining so woodcutting yews, even then you don't make much though.

Buy membership

Thats why you need membership :P

I'd suggest Yews or Rune Ore, they made me 10m+ a few years ago

I'm F2P, currently going for 85 mining, at 80 now. I'd say go for 85 mining for runite. You can either mine coal to 85 or iron. Coal-More Money. Iron-More Speed. I suggest using the dwarven mine and use the resource dungeon bank for either ore. Though you need 15 dungeoneering to use the resource dungeon.

He clearly states he doesn't want to be a member yet people still suggest it. -.-

I noticed you said best way to make money, not fastest. In my opinion, the Fist of Guthix minigame is a pretty fun way to make money. Granted, it's obviously not the fastest but it's one of the few things in F2P I'd bother doing for extended periods of time.

Chop Yews or mine Runite, slow but makes money over time.