Originally Posted by Chombi1

The only tricky part of aligning the tire to the rim, comes at only the last eigth or quarter of the tire you have to stretch over the rim. You can align the tire easily before you get to that point. After you get that last portion of tire over the rim, You can still move it around with your fingers to align it, as long as the glue is still fresh , But in my experience, it gets itself mostly aligned just from the tension from the tire itself.
You can find enough videos in the net to see how you do the installation. Most of them have pretty much the same ethod of doing it.