Trading for profit is very slow in the beginning, even with a Hauler. You're best bet starting out is to simply head to RES's and bounty farm NPC ships. You can do it in a Sidewinder, but an Eagle is better, and Viper better still. As long as you register some damage in the 30 seconds before the target hit's 0% you'll get the bounty.
I wouldn't bother with trading as a source of income until you can get a Type 6 or better.