1. have it clean
2. have it clean
3. make damn sure its clean
4. make damn sure it has no residue of cleaning stuff whatsoever left
5. fill hot water to just under the valve, or a little less
6. fill filter without any tamping whatsoever(!), but little overfilling is okay
7. screw together
8. put on medium heat
9. watch it
10. when the coffee comes flowing off the top, watch closer
11. the first signs of spurting - take away from heat
12. serve
(what worked for me quite well was continously taking it from heat until I saw that the flow reduced and putting it back on heat for a few seconds - that way it didn't overheat). I have no idea on the optimum coffee per litre ratio for these beasts, though - managed to survive with just trying there
13. clean that darn thing
14. if its aluminium, make sure it's clean
and dry before storing away, otherwise you'll get funny stalagmites and stalagtites in the lower part. have fun and vary as necessary