Petitioning Spirits, not evocation . . . just petting the kitty, not taming the tigers Options

Does anyone have any experience in petitioning a goetic spirit, instead of outright evocation . . for a more "practical" type result. If so, any experiences you can relate?

I'm sorta trolling here, as I'm in the process of starting a goetic petitioning work . . . and am simply looking for ideas and creative approaches.

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Well, I thought demonalotry was worshipping demons . . . I'm specifically not intending on worship.
Though I would be giving patitional offerings . . . in trade for request-service (and a bit of lite relation building).
My intention is toward a non-paradigm specific method of lite contact. But not worship or personal subjugance . . . though, admittedly, oblational offering.