Injections - Sites
The most important requirement is to keep consecutive injection sites well apart. Injecting twice in the same area without giving it time to recover is a recipe for trouble. The easy way to achieve the required separation is to select twelve sites, for example 3 on each leg and 3 on either side if your abdomen. Use the upper site in each of the four areas first, then the middle, then the lower. This means that adjacent sites are not used closer than five weeks apart, and the system lasts twelve weeks. At which time you select a further 12 sites say two inches to the right of the originals and repeat the procedure. It's easy and effective! Another option is to treat twelve sites like a clock face and move the 'time' by seven 'hours' each time. My experience leads me to prefer sites on the abdomen, as they seem to be less sensitive than others, but don't go close to the navel as there are too many blood vessels there. The other big advantage is that you can get to this area without a ridiculous strip-tease. Whatever you do don't inject into your arms. The drug is 20% less effective if you do!

Injections - Techniques
There are two schools of thought as to whether cleaning an injection site with alcohol is necessary. Some phlebotomy departments do and some don't. I personally take the view that if you are going to take the trouble to wash your hands and ensure that everything you use is clean, then it makes little sense to inject into dirty skin. I clean the spot thoroughly, and I have had no problems. If you choose to do so make sure that you allow plenty of time for the area to dry as the slightest trace of alcohol will make it sting like hell! It is a mistake that you are unlikely to make more than once! Don't forget that interferon has to be stored at low temperatures, and the best place is a 'tupperware' box in the salad draw of a domestic fridge. Don't put it where it might freeze. If you try to inject it while it is still cold you will regret it. Hold it in the palm of your hand for a minute or two and let it warm up. Do NOT shake it!
Regardless of what anyone else says, my personal experience has shown that inserting the needle slowly and gently gets the best results. The slower the better! In my view all other approaches should be reserved for the dart board! Leaving the needle in for ten seconds after you have finished injecting reduces the amount of very valuable drug that leaks back up the needle path. Try not to touch the site for a minute or two as this allows it to settle down. The moment the needle leaves your body it becomes a hazard to anyone else, so get it straight into the sharps bin. Don't attempt to cap it or put it down.
There is quite a good guide to self injecting on the drug manufacturer's site which is worth a look. Bear in mind that your interferon may not come in the same packaging as they show. See Pegasys info and video
I strongly advise doing your injections two hours before bedtime. This is because not all of the Pegylated Interferon is slow acting, and there is a peak about 3-5 hours after injection. If you take two paracetamol tablets and go to bed two hours after your injection there is a good chance that you will sleep through the worst of the side effects, as the peak of the paracetamol co-incides with the peak from the interferon. Why suffer when you don't have to?
Paracetamol (Tylenol) can be very effective in suppressing a lot of the flu-like side effects from the injections. To get best results it is best to take it before you get the effects. The interferon has a double peak in its curve, the first peak being close to the injection time, and the second after either 50 or 80 hours after the injection depending on the type of interferon. (PegIntron = 50 hours, Pegasys = 80 hours.) If you find that you are getting flu-like symptoms at these times, try taking paracetamol during these times the following week, and hopefully it will prevent them occuring. Don't exceed the maximum dose stated on the packet without your doctor's permission. (Paracetamol is known as Tylenol in the USA, and has a generic name of acetaminophen.)
Incidentally, on one of my courses of treatment I was given Indomethacin to help suppress the flu-like side effects. It took me some time to work out that the dreadful stomach problems I was getting were due to the Indomethacin and not the rest of the treatment. Treatment for side effects also has its own side effects! I changed to paracetamol and the problems went away. If you are offered Indomethacin be aware that it is a powerful drug, and can cause problems of its own.
Travelling by Air
On the subject of injections, should you plan on flying anywhere, remember that your injection equipment is treated in the same way as scissors and knives as far as airlines are concerned. Needles are not allowed in hand baggage. My suggestion is to put everything bar the drugs themselves into baggage going into the aircraft hold, preferably duplicated in more than one bag in case one gets lost. Carry the drugs with you in an insulated container, preferably packed with a cold block. The holds of aircraft are not pressurised or heated, and the drugs could be damaged. Take extra doses with you in case of accidents or delayed flights, and take the drug data sheets and/or a doctors letter just in case you need treatment abroad. Don't forget that commercial aircraft are not pressurised to 'ground level' pressures, and if you are getting 'breathless' symptoms after exertion you may well get them on the plane. Don't panic! It will go away! Incidentally, if you go to any high-altitude destination your short-of-breath symptoms are likely to be worse.