Right, this is my method. I didn't invent it, it's just what I use and has worked flawlessly for me. No air loss, no burping, no punctures.
You will need:
1. Some very fine sanding blocks. Preferably those sponge ones. Available from any DIY shop.
2. Some strong, clear cross-weave or mono-filament packing tape. The cross weave stuff is usually very wide but can easily be torn lengthwise (like duct tape) to get the right width for the bottom of your rim.
3. Some PVC electrical (insulation tape)
4. Some washing-up liquid and water
5. Some Stans solution or similar latex based sealant.
6. A CO2 inflator or compressor. (I never have any luck with the initial inflation and seating using a track pump despite what other folks claim. Maybe I just have weak arms.)
7. The presta valves from some Schwalbe tubes or similar. Basically, ones with removable cores so you can easily top up your sealant.
1. Remove tyres and rim strips from wheels.
2. Wash wheels and dry well.
3. Sand the inside of the rims to make sure they are perfectly smooth and clean. Use some very fine sanding blocks. You can get these from any DIY shop.
4. Get packing tape to fit the width of the base of your rim. It should ideally be slightly narrower than the insulation tape although I have used this method very sloppily in a hurry and had no issues whatsoever. Stick the tape around the circumference of the rim with an overlap of about 100mm. Make sure it is pressed down well and completely covers all of the spoke holes.
5. Do exactly the same with the insulation tape. It should ideally be slightly wider than the packing tape and again press down well.
6. Cut the valves from the tubes so that they will seat well and make a good seal against the tape.
7. Carefully cut a hole in the tape so you can insert the valve into the rim and do it up nice and tight.
8. Put your tyre on the rim as you usually would, get loads of nice foamy washing up liquid mixed with water around the bead of the tyre.
9. Add your sealant to the tyre.
10. Use your compressor or CO2 inflator and just blast the air into the tyre. It has always inflated and seated for me first time. Get it up to a good high pressure. You can always let some air out once it is well sealed.
11. Swill your solution around the tyre, getting it up to the beads to make a good seal. Hold the tyre vertically, side on and swill using a forward-backward motion whilst rotating the tyre.
12. That's it. You are done. Do your other wheel and go and have a nice cuppa.
I have successfully used the Schwalbe presta valves for well over a year but recently I splashed out on some of the Stans Valves to replace them. These work just as well, no better, no worse. They are the "standard" ones, I bought them here: http://www.justridingalong.co.uk/?product=58
The tapes I bought from here: http://www.tapes-direct.co.uk/index.php?main_page=index&cPath=148_193