Had a couple things to add, if this thread isn't too dead...
• Damping is a technique that helped me a lot: It's putting your thumb or fingers over the bowl while you draw, nearly blocking air flow. It will help to stoke the ember.
• Try damping before and after tamping too help keep the bowl lit. And as mentioned by Kola, puffing while tamping will help too.
• Continually puffing and puffing to keep it lit actually works against you. Often a bowl will burn unevenly if you do this. I ensure the bowl is burning evenly, which satisfyingly produces more smoke too. I use my tamper to "level" my bowl as needed, though it does usually require a relight afterwards.
• Lastly, don't worry about relighting, do it as you need. Use a zippo if your blowing through matches, just give the fumes a second to burn off.
Just my 2¢