Read Curse's FAQ on the general forum (sticky)
It seems he studied my airline, too
Don't be influenced too much by others. My airline is a very bad example, because I was late in the game and had to use a strategy that doesn't consume much time.
So don't hang up yourself on a special airline. If you want to be successful, develop a strategy before you join the gameworld and stick to this strategy. If you decide to go for 737 classic, only order 737 classic and don't go after A320, 737NG, MD-80 and whatever because they are available when there's no 737 classic for your fleet in sight.
Patience is the key.
If you feel more secure with AirwaySim you can change strategies or try something different, dictate your opponent or play with him... but that's nothing a new and/or unskilled player should do.
Also leasings are a very tough thing. I normally try to avoid them and I don't suggest anybody to lease out always as much as possible. It can and it will bring your airline down if you don't know exactly what you are doing.
Read the FAQ, read around in the forums and when you have specific questions, don't hesitate to ask here or drop me a PM.