I use a site called: steembottracker.com to select which bot I will use. You send them SBD or steem according to their prices and put the link to your steemit post in the memo.

I must give a warning, most bots will return less than what you sent them. So, you'll be losing SBD or Steem potentially. You'll also need lots of SBD or Steem to get a big enough upvote to make it to the trending or hot page.