There are many "heaven"s, as I see it...
One of these, which I go to for information, is the Realm of Spirit Animals. I do the usual preparations for a journey, then halfway up (I use a ricketywooden ladder: my teacher suggested a ladder when I was very young, and I haven't rebuil it yet...It's had many years of almost constant use, and I think that it's time to repair this mental tool...), and though the ladder continues (both up, down, several other ways...) I swing through a little hole and come up underneath an enormous tree. The place is filled with animals (of course) and I can find out from them, generally, whatever I need to know. There's usually something I do in return; I was taught (and believe, since it works for me) that there are essentially five (5) KNOWN ways to relate to a spirit.
The first rule, as I believe it, is that no matter what, in any dealing between entity and entity, the relationship MUST be made clear for there to be useful communication. It doesn't matter as much WHAT the relatioship is (although I have preferences), so long as it is clear. The five ways I am aware of are:
» Binding by Gift.
» Binding by Love.
» Binding by Trade.
» Binding by Spirit.
» Binding by Weapon.
Since the last one is, in MY way of thinking, least desireable, we'll start there: Binding by weapon, for me, is only used when a spirit or entity comes to me with something nasty planned, and only if there is no other way. It is kind of like putting the genie in the bottle (the old Arabian Nights Genies were very tricky, and would just as soon devour someone who lets them free as grant them wishes...): first, you must have superior force, and superior will. And Plenty of Reasons...
Binding by Spirit is MUCH more preferable: This is the link you have with your spirit animals: A link from like to like, regardless of form. It usually HAPPENS to you, rather than you CAUSING it to happen.
Binding by Trade is offering something in return for what you wish to receive. Not as wonderful an experience as Binding by Spirit, but still worthwhile. It is necessary to find some entity willing to trade, however, and for this the Realm of Animals is where I use it most. After a while, you can get into a routine, whereupon in becomes
Binding by Gift is when the shaman leaves a gift or gives a gift, in expectation of needing a favor later. This can be considered the case when a spirit comes to you for help, but generally I classify that as Trade, since it is the same as trade, just the other way around. Binding by Gift, you do the thing first: If I need information that I think the Squirrels, for instance, in the Animal Realm can offer, I'll leave out a selection of nuts underneath the pine tree in the fron yard, for I know that there are squirrels which frequent it. Then, later, I'll go up to the Animals and ask for what I need.
This originally started as Binding by Trade, where they'd tell me the information I needed to know, and then say, "In Trade, you can leave nuts for the Little Brothers." Now, I do it aforehand, knowing. This is a much more comfortable relationship than Trade, as Trade is generally a one-or-two-time thing, while Gift is something much more meaningful and long-lasting.
Binding by Love is actually entering into a friendship (or deeper) with a spirit. Most of the shamans to whom I speak agree with me that the relationship they have with their Spirit Helpers/Guides is a love or lover relationship. Some explain that they are soul-mated to their guides. This makes sense to me, and is the last form of relationship of which I am aware in this context.