OK - firstly stick at it - it can be alot of long, hard work initially
you should have a stardrive (L4 i think) - which will let you trade between cirrus Minor and Tau Ceti. This is the only drive that will let you jump systems while carying cargo. Hit f6 to bring up the galactic map, use your mouse to click the system in range, and click the stardrive icon (top of the drive icons on the left of the screen) When you're cash improves you will be able to upgrade you stardrive - L8, 24 and 40 are all available at a cost.
use a pen and paper, and check the system trade reports for what is available within your price range, making a note of where you can buy/sell items, and keep running the trade route until its exhausted - fipro/infimp around when your cargo is empty to check. as your cash improves you will be able to afford better cargos with better profit margins.
gradualy build up your ship specs - increasing cargo capacity and stardrive level as and when you can afford it, remembering to make sure you have enough cash left over to buy a cargo
eventually, build up to a gal freighter - decent ship with good capacity and speed - ship stats can be found here:
http://theuniversal.net/forum/viewtopic.php?t=4144 (you may find something you like the look of better than the freighter - your choice, but if you're getting into the trade side of things I would recommend it)
One thing to remember - cargo extensions and stardrives are not cumulative - only the biggest will work. (so you can't buy 3x10ton extensions and carry an additional 30tons)
You can sell them back at various stations, rather than having them in your ship inventory, but dont expect to make a profit on them.
hope all this helps
)
(probably nothing for a high lvl 
