Bees wax. Your best friend for hand sewing great great grandma used it, great grandma used it, grandma used it, mom used it, that makes it perfect for me. A small cake, sold online, will last you the rest of your life! I do keep mine in a zip closure Baggie because everything sticks to it. I keep my needle threaders in the bag with it because that makes them easy to keep track of.
Run your thread over it a couple times, then before tying the knot, pull it gently through your two fingers or a scrap to remove any clumps.

I was having the same problem and started threading the needle like Nammie said. I haven't had the thread not since. I didn't thick it could make such a difference but it did.

I run mine thru beeswax....some store has them in small round plastic see thru
Container. I think it got knotted only once on me as I twisted thread around when I
Wasn't paying attention.

I was taught to do it like this...if you're right handed...push your needle up through the fabric , then put your left thumb over the hole the thread is coming through...pull the needle with your right hand and keep your left thumb over the hole...never fails! If you're left handed, just reverse.

That little plastic beeswax holder that has grooves cut out to run your thread through is wonderful for making your thread smooth and pretty much tangle free. Also, letting your thread unwind itself is a good practice as mentioned my others here.

I have found that before threading the needle, run the thread several times thru a dryer sheet, no more knots, don't know why but it works for me :)

I got on pretty well with knotting the other end of the thread but still got the occasional knot. I went for a rummage in my mum's beading supplies and discovered that she had some thread heaven! Hurrah! So now I am in thread heaven! It just glides through so smoothly now! Awesome!
Thank you so much to all of you for your advice and tips, you've made hand sewing relaxing for me again!

Tartan explained the "twisting" perfectly. It's just another way to "deal" with it! :-)

Prayers that you feel better and can get back to your machine.

cpfrog

Thread Heaven is da bomb. Best stuff ever. To make sure I knot the right end, I thread my needle before I snip the thread off the spool, and THEN cut it and knot it immediately. There have been too many times when I've cut the thread, then dropped it. Now I don't know what end was cut!

You guys are GREAT ! Wonderful tips!