You didn't say what bike you have. I would follow your manual if you aren't familiar with this. However, here is what I do. Asuume that you have just regreased your bearings, tighten hand tight then tap about 1/8 of a turn more, move triples back and forth from stop to stop. Loosen and then retighten finger tight plus 1/16 turn, just a little past finger tight. reassemble the top t-clamp and enjoy. If you tighen more, you will damage the bearings. They only should be tight enough to ride their race. A good test is to support the front end off the ground, grap the front wheel and wiggle it. If there is ANY slop or movement other than the normal side to side from turning the steering, then the bearings aren't tight enough, or are out of spec to the race. If the slop is in the front wheel to axle, then the front wheel bearings are shot.