This tutorial explains a fast and simple method for threading your needles. You must be able to see the eye of a needle in order to do this. If you can’t see the eye, try a self-supporting magnifier.
Step 1: Place your thread between your thumb and first finger of your non-dominant  hand and pinch your fingers together. Make sure the end of the thread is near your fingers. Hint: Use a dark thread if your skin tone is light and vice versa.
Step 2: Pull the thread down between your two pinched fingers until you can *barely* see the thread end. It should look like a small black dot between your two pinched fingers. Do not leave a little tail, the thread must be buried between your fingers with only the tip end of the thread showing.
Step 3: Position your needle over the thread, with your needle eye lying horizontal just above your thread tip.
Step 4: Place your needle eye gently on top of the thread and begin pushing the needle eye down over the thread. Be sure to keep pinching your fingers together, as it holds the thread in place and allows the needle eye to slip over it.
Step 5: Continue pushing your needle over the thread. Your needle should disappear down between your two fingers - which you are still pinching together.
Step 6: Release the needle by gently rolling your two fingers upward and towards each other without letting go of the thread. Pull the needle down and out from between the bottom of your two pinched fingers. Your fingers should now be grasping only the very end of the thread.
Step 7: Finish! Pull gently on the thread - you should have a threaded needle!

Summary:
Start: Place a thread between your thumb and forefinger
Pinch: Pinch the thread and pull it down until barely visible
Position: Position your needle eye horizontally above the thread
Place: Place the needle directly over the thread and push down
Push: Push all the way down between your pinched fingers
Pull: Pull the needle out below your two pinched fingers
Finish: Finish by pulling on the thread