If you're starting from scratch, my strategy would be
1) Make a list of the prices at planets around Lave. Use this to find a
likely trade route - 2 or 3 safe planets where you can make a reasonable
profit on each leg.
2) Milk it - go round and round for as long as possible. The prices will
stay constant but the amount of goods available will fall.
3) Move on. The planets tend to form clusters, and there's generally a
good route in each cluster. Leesti rings a bell as somewhere I made a
lot of money, but I can't remember exactly where it is.
Other hints:
1) Sell your missiles when you start. At $30 a go you can't afford to
use them until you're making over about $40 per run, so you may as well
flog them and increase your capital. Keeping one is useful as it lets
you I.D. other craft.
2) When buying add-ons for the ship, remember to leave yourself working
capital (trading money). I would recommend more missiles, an ECM and
fuel scoops, in that order. The ECM stops you dying. The fuel scoops
let you pick up cargo canisters, escape pods (sell as slaves) and
pieces of asteroid (blown up with normal lasers, but you have to get in
quick before the bits disperse). Make sure you have some room in the
hold before trying this. It's not really worth going to the star to get
fuel early in the game, as you'll get too much grief from bandits.
3) Learn to dock manually, and forget the docking computers.
4) Think carefully before buying the tribbles ...
Bounty hunting (deliberately going looking for bandits) can
be good fun + much money, but you need a big laser and energy unit.
I hope this is some help. Unfortunately I haven't touched the
game since April, but having written this I'm sorely tempted to dig it
out again...
Henry