Step one - get some safety goggles.
Step two - get some mechanics gloves - something thinnish, but tough.
Step two-point-five - get a pair of Vice Grips and have them handy.
Step three - lightly grease the length of the spring.
Step four - coil the spring loosely by hand.
Step five - hold the coiled spring in one hand, loose end on top.
Step six - pull the loose end out, allowing the coiled bit to tighten up in your hand. Hold it tight once you've reached a point where it is smaller than the housing.
Step seven - holding the coiled bit tightly, loop the loose end around as many times as you can until you're left with a few inches of the loose end. Repeat from step five until you've used up the loose bit and the coil will fit in the housing.
Step eight - now, from the exposed side of the spring, clamp the vice grips at about half the profile width of the spring, about in inch from the loose end of the spring.
Having a helper may be helpful, to adjust and apply the Vice Grips, etc. Do not clamp the spring too tightly, as you may crimp the spring. Snugly will work just fine. With the clamp tips at about half the width of the spring, you can insert the spring into the housing. Seat it firmly in the housing before releasing the grips. Make sure you insert it the right way - the loose end should extend off the coiled spring in a clockwise direction.
