Commodities trading in anything less than a T-7 isn't the best use of time if you're looking to maximize credits/hour
If you're looking for great ways to make cash there are two options for you at your current stage. (Until you can afford a Python)
Bounty Hunting:
In a good RES you can pull in 4-5 Mill an hour in your Vulture, Just keep resetting the RES (logging in and out, or SCing in and out) until you get Anacondas, Clippers, Dropships, Pythons ETC. There seem to be several different types of RES spawns
-Small Ships, Sideys and Eagles almost exclusively.
-Small-Med ships, Sideys, Eagles, Vipers, Haulers, Cobras.
-Small-med with an occasional Large. Same as before but you'll occasionally see an Anaconda or Clipper.
-Almost exclusively Large ships. This is where you can make some serious cash. Some of the bounties on these guys run upwards of 250k per kill. The lowest bounty I've seen in this type of res is ~45-50k.
In a Vulture, load 2 Pulse Lasers, Target the Power plant on these big ships and go to town. The lasers let you stay in the RES without needing to Re-arm. They also do the best for getting through the hull to hit the modules.
Rare Trading
Your Type 6 or a Cargo cobra are both excellent ships to do this with. Fit them with decent FSD's and ~80T of Cargo and you can pull in 2-3mill an hour, More if your lucky on the Allotments you get from the stations, and if you're FAST. The bigger the FSD the better your profit will be on this. It also helps if you're quick about docking/refueling,supplying/undocking.
There are plenty of good guides out there regarding these rares.
http://www.reddit.com/r/EliteDanger...w_player_guide_fast_money_rare_resource_trade Is the most comprehensive I've seen.
The most Common route involves picking up rare commodities from Lave, Diso, Leesti, and a few other systems around the old worlds. and Flying ~160 LY out to Witchhaul, and 39 Tauri to sell the batch, and pick up a new set from surrounding systems. There are plenty of others out there though The spreadsheet attached to the link I gave has a fairly comprehensive list of the known rare commodities and where to get them.
Once you get to the T-7, regular Commodity trading is comparable to the above suggestions. It doesn't take too much longer from there to get the Python. Once there you can either kit it for combat and keep doing RES farming. Or you can kit it for Trading.
Lastly, Community goals can be a HUGE bonus for you.
I did 2 runs in My Anaconda during the Wolf 406 CG (~800t of Cargo) and decided that flying 3k LS to the station for minimal profits wasn't really worth it for me - So I stopped.
When the CG finished, I was in the top 70% and got a 6 million credit bonus.
In a t6, a 6 million credit bonus for 8 trips would be STELLAR profit.