I've only played for about 6 hours so far, and I've made minor profits (like, 100 credits per unit) trading, but I'm feel like there's got to be a better way of doing this that I just don't understand. Spending 10 minutes running between stations for a 400c profit just doesn't seem viable.
The answer to this question about how to use the Galaxy Map to view trade routes might be part of the answer, but I'm sure there is more to being a successful trader than that. Obviously, upgrading to a ship with more cargo capacity would help, but that costs a lot of money and 400-800c per trade seems like a slow way to get there.
Note that I am not opposed to using third party tools or websites that aggregate trade data.