What a coincidence, just wrote about it
here.
Anyway, as I see it there are five different methods of ingestion, whereas I've tried four;
1. Smoking/Vaporising
It requires a lot less than with the other methods, but according to personal trials, it's still a bit too much for ordinary smoking (the smoke is quite harsh). It is possible, without a doubt, to get effect from it, but it is a tough on the lungs. Vaporising seems like a good idea though, and changa sounds like a great idea!
2. Tea
Simply let some dried herbs sit in hot water for 5 minutes, like you normally make tea. This is a very weak method of ingestion, since not much seems to migrate into the tea. It taste mildly and is very enjoyable, especially with some milk. But I have to say, if you want noticeable effects and not just sleep-aid or a nice cup of herbal tea, this may not be the method for you.
3. Brew
No, this isn't the same as tea. Here you let anything from a couple to 20-ish grams sit in boiling water for a certain amount of time (tip: experimentate). After it's done you can either choose to filter out the empty herbal material or let it sit and simply avoid drinking it. The herbs are quite dried of taste (and probably alkaloids too). Something one should note though is that you often get a quite decent amount of brew, at least I for one prefer to make about a liter (of 15g) I then pour up into teapot from which I drink over an evening. The taste is very bitter though, but I enjoy it more than the tea. Really relaxing, recommends highly!
4. Chew
This would be something to try with non-dried material, since it isn't that much of a blast with the dried form. It does not taste nice, and after you've tried chewing a couple of grams you'll understand what I mean. This is mainly to get it active sublingually (which I haven't confirmed) but also to get all the material down there, so remember to swallow. Note that chewing and then swallowing is the most effective method (except smoking), but also the least pleasurable one (at least in my opinion).
5. Soaking in alcohol
This is an interesting one, mainly because I have not tried it. In theory it involves an amount (like the brew) of herbs that you let soak in wine or vodka (high alcoholcontent). The point is that the alkaloids should be much more soluble in ethanol than in water, thus increasing the bioavaibility from both the tea and the brew. After an hour or so, remove the herbs and enjoy a 'slightly' more bitter alcohol beverage.
Good luck, and remember to try them all to find your way!