#1 Patience Patience and more Patience. There is NO WAY to make millions over night. This is the biggest stumbling block I come across. If you try to run the race like the hare you will lose; you need to be the tortoise - slow and steady wins the race. Go for that big score and you will only be disappointed. Craft lots of little things at a modest profit, they will sell consistently and your coffers will grow.
#2 Set a goal and stick to it; "keep your eyes on the prize" - if you want to make a million credits do not spend a hundred thousand on some new shiny you see someone wearing. which leads into...
#3 do not spend any credits on anything you do not absolutely need. You'd be surprised how much saving your credits impacts your credit making process.
1. My record was over 10 mil one night (and i bet there are better ones) so cut the poppycock.
If you manage to get a rare thing before everyone else then you can make a lot in a very short time.
2 and 3 on the other hand are very true.