alright i could pop my hood 2 days ago and i tried to pop it yesterday to show my friend something and it wouldn't go what do i have to tightne so that it will work again?

try having someone push down on it where the emblem is while some one pulls the cable, my si was like that till i adjusted latch

yeah the old punch on the emblem trick usually works wonders, to solve the problem tho, make sure the cable for the release is still tight but not to tight so it pops right.

how do i tighten the cable?

Here ya go....

The hood cable is not adjustable.
to adjust it you will need to adjust the hood latch (part that you are banging (under H emblem) on inside of hood. Loosen the screws and move and tighten.

that should solve your problems.

the hood cable IS adjustable if you remove the surround that covers it inside the car, its like tightieng a nut.