It's easy to set up a bp.tf bot as it's an easy way to get a starting in making profit. It can be pretty confusing to set up the bot initially though.
Basically what you're doing is buying and selling low cost items for slightly different prices, turning a little bit of profit each time. This profit can then be used to buy and sell more expensive items that will give much higher profit per trade.
Doing all this can help you to get started into unusual trading though, with keys being over 36 refined now, getting one scrap per trade requires ~300 trades to get just one key profit. The time for trading is largely over, but I'm glad if this helps you.