This video by Jewish Pathways explains how to tie tzitzit to a tallit better than any other I’ve seen. It’s the one I always refer to:

Here are a couple of my own tips:

• Each time you start a new set of windings, pinch the hanging tzitzit threads together just below the knot. Make the first winding slightly tight, then let the next windings fall naturally around the hanging threads. Make the last winding slightly tight, like the first. After you’ve made the next knot, the windings will relax into a neat, uniform look.
• After each set of windings, return the shamash to the three-string set before counting the number of windings. This helps eliminate the uncertainty of whether that last winding went all the way around the hanging strings.

Thanks, Jewish Pathways!

(Video: JewishPathways via YouTube | Alternate spellings: tzitzit, tallit)