Well, I personally just put some powdered fenugreek on my tongue and swallow it (usually). But, it's a good thing you asked, because you might want to do something else. The reason is that if you don't get it down your throat fast, it's going to stick to the roof of your mouth for a long time, like powdered gelatin would. Plus, it has a strong taste. I like it, but you might not. So, you could easily mix it with something. It goes great in ranch-like salad dressing. I make my own with it, sometimes. So, preparing food with it is a definite option. I'm not sure if it still works after it's cooked, though. I never tried it like that.
So, I used to use tablets from Swansonvitamins.com. Those work. It's not too much or too little, using the recommended dosage. A teaspoon of fenugreek is actually quite a lot. It's probably not enough to make you smell horribly like curry, but it is a lot. I'd say maybe a fourth of a teaspoon. You might need more or less, though, depending on your situation.
I make home-made salad dressing sometimes. Here's an example recipe (I don't know the proportions offhand, but I'm giving ingredients):
* a little fenugreek (to taste)
* lemon or lime juice (to taste)
* sesame seeds
* I'm not sure what else I used, but you could improvise.
Fenugreek is actually what they use in a lot artificial maple syrup to get the maple taste. It works in some sweet things and some savory things. It's a great spice and herb.