I've had 99 hp for a while, but if you just want hitpoints, I suggest doing pest control with a clan, or perhaps soul wars. Otherwise you will just have to train combat until you reach 99, which slow.
Soul Wars ban rate is alot higher than that off Pest Control, But for speed and fast xp i reccomend Soul Wars, Pest Control is ideal if you want a few quick levels i wouldn't reccomend it all the way.
As others have said, soul wars is faster. There are some bans that happen there, but there are hundreds of botters botting there every day. You probably wont get noticed. Back a couple years ago when there wasn't Soul Wars, I got 99 hp through pest control.