get someone else to help you.... you want harness long enough on frame so the curve of shoulder strap and fattest padded part is actually over curve of shoulder and not still down your back.... put some weight in pack snug up hip belt then adjust shoulder straps till they take some of the weight but still leave some on hips... a small gap between top of pack and back/shoulders is good but too much and it tends to pull you backwards,move COG backwards...... how you actually LOAD THE PACK makes huge difference too... the majority of weight should be as near to your kidneys as possible,EG down low and close to your back..... nothing worse than out at front or up on top..both affect your COG drastically.
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