Hi Jupiter. Bit involved but,
1. Piece timber bout 3" x 2" x 12" long.(base)
2. 4 off 3" nails.
3. Hammer 2 nails into timber base at 45 degree angle, so that they overlap each other at about 90 degrees, hammer the other 2 nails at the required distance to hold the laser... You are making a 'V' block/holder/cradle/thingy...
4. Take outside & set-up about 6' from a blank wall.
5. Place laser in 'V' cradle.
6. Turn it on & slowly rotate the laser in the 'V' cradle.
7. Watch the dot on the wall. If it moves in a circle, it needs collimating.
8. Be very careful when doing so, as you can break the assy inside.
9. Adjust as nec. & keep rotating after each step.
10. When the dot does not move off centre, you're done.
HTH....
L.
ps. All up costs = zilch.