[janoskiss (Steve H)]

Originally Posted by doppler

Here's a step by step guide.

http://astro-baby.com/collimation/as...on%20guide.htm

That looks like a good one: thorough but not over the top detailed (and sticks to simple Cheshire). It also shows the (apparent) offset of the secondary: what should appear centred and what does not need to be once collimation is completed.

@OP. It's not hard but you've got to do it systematically from start to finish. Just so you know what to worry and not worry too much about: The positioning of the secondary is least critical (you can eyeball it and/or use a ruler), its orientation is second least critical (get it close enough looking straight through the focusser) and the orientation of the primary is most critical (be as precise as you can be with Cheshire).