if you eat the non toasted varitey then it is as simple as getting the proportions right but i use 3 cups oats 1/2 cup weatgerm or bran flakes, 1/2 cup coconut, 1 1/2 cups of dried fruit, 1 cup nuts, 1/2 to 3/4 cup of brown sugar, mix and keep in air tight container. Change proportions/ ingredients till you get it how you like it.
Toasted ( our favourite) is much the same sort of proportions of oats and coconut, 1/2 cup weatgerm, 1/2 cup of bran (or i leave it out sometimes as is alot of roughage and this is yummy so if you have big bowls you will know all about it!)1/2 cup nuts, 1 cup of whatever mix of seeds makes you happy. mix together in a big roasting tin. in a saucepan mix 1/4 cup oil, 1/4 brown sugar, 1/4 honey ( i mostly use golden syrup because is yummy but both good), heat all this up till sugar disolves.
Mix it throughly through the oats and stuff bake at 140-150 for 30-40 mins or untill browned all over ( stir it every so often so everything gets a shot to get brown, you kinda get the knack) after that add whatever dried fruit you want.
both of these are jump off points and it is different everytime it is made hugely dependant on what is in cupboard/ on special / what i feel like!
but homemade is sooo much yummier if you have the time/inclination to make it and the kids love to help ( i used to make it with my mum and loved getting to change it to how i liked!).
hope this helps