I'll make a brief summary, maybe it will help...
In Partial Hanging, the more of your weight you can apply, the better (like in standing or kneeling posture)
I recommend reading the info and looking at the drawings with all postures in these threads:
Calculation of tension exerted on a ligature in incomplete/partial hanging
AreWeWinning's detailed explanation about the positions in Partial Hanging
About feeling discomfort and cannot lose consciousness...
• If you feel a lot of pressure in your head, as if it's about to explode, it means you're just compressing the jugular veins. And not the carotid arteries.
The goal is to block the carotid arteries, which supply oxygenated blood flow to the brain. They are deeper in the neck, and blocking them correctly will allow you to lose consciousness quickly (in less than 15 seconds).
• Points to analyze (what could be wrong?)
- it could be the position of the body (you are not applying enough of your weight)
- the position of the knot in the ligature (the noose knot with the stopper knot should be behind the neck, in the center)
- the position of the ligature (rope) in your neck (goes under the jaw. More or less at the height of the Hyoid Bone, which is above of the Adam's apple)
- the rope is too thin, it hurts or doesn't apply enough pressure. You will need to buy a thicker one.