A lot of people have problems with tangles and twists when they put new line on their spinning reel. Here is a method to prevent that so you can get it right the first time. The concept that you need to realize is that each spinning reels bail spins in a certain direction. It could be counter clockwise or could be clockwise. It depends on the brand. The same is true with a spool of fishing line.
What you want to do is take your spool of fishing line and set it down on the floor. Take your reel and point it directly over top of the new spool of line. Spin the bail slowly, and you will see the direction of the spin (clockwise or counter clockwise). Make sure the line comes off the spool in the same direction as the bail rotates. Example: If your reel spins clockwise then make sure the line comes off the spool clockwise. This way the line goes onto the reel the same way it was on the spool, thus preventing line twist.
See the video for a visual demonstration.