Practice makes perfect-ish? If I remember correctly, I went overkill with this blanket and used a russian join, which does not create a tail, though you have to get used to calculating exactly where the join will happen on the yarn so that your stitch colors do not bleed together.

Typically, I do a standard type join, making sure to work the ends in as I go. If you work your tails into one or two stitches (rather than weaving them between the stitches, as is normal to do at the end of the project) it almost ties them into place, securing them. I prefer to not have tiny lumpy knots in my blankets, so this seems to be the way to go. This comes back to bite you if you have to frog anything.

If you work the ends into the same color (which might mean carrying the yarn to the next row up, rather than the next stitch), then the ends become invisible.