R1ck

The curves really pains me the first time I tried to do it. I more concerned about my map shape . I need to play more wads so I can adapt. 

Yeah. That definitely will help you for absorbing more inspiration.

Studying maps that use shapes well really helps.

Also, I think one of the most important ideas is that you can create rooms by stitching together simpler shapes, or even just lines. Here's a quick example. I copy/pasted every time I did something meaningful, so that you can see the area as it evolves.

http://i.imgur.com/d3ngiPs.png

I use a scheme that has a lot of 45-degree angles and some curves. 

This isn't how I'd make a map these days, but it should demonstrate the concept I have in mind.

If you come across areas in a map that you like, you should open it up in GZDB and think about how you might draw those shapes yourself. You can even draw on paper while you're looking at it in the editor.