Depends on who you are calling and why you are calling them.
I absolutely loathe set scripts and have never used them. So I basically clean/banish and prepare my area of whatever kind I am using, which might involve just sitting here or making a circle or putting up a triangle or mirror or whatever. I then gather tools and consider correspondences if I even want to use them and then I just call their names and speak to them. I mean, this doesn't have to be a big deal, assuming you are a beginner and starting with say angels or something 'light'.
It can be as easy as inviting them and saying good morning and asking a question; getting an answer (a real one) and acknowledging them or thanking them and then telling them they are free to go (again, assuming a 'light' entity here) and cleaning up afterwards.
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