You could do anything you want basically. In my last standard ritual, after burning the paper and talking to Satan, I also recited a prayer I have made myself. You can do Satan's Absolution during it as well. Mantras. Whatever you want.
Regarding enochian keys, I personally don't recommend doing them, here's a quote in which Cobra explains its origins:
HP. Hoodedcobra666 said:
While I do not believe the Enochian keys are so bad, the thing is, they were created by the characters stated. They do not reflect the most powerful spiritual language, nor the language of the Demons. Enoch-Ian is actually the language claimed of Enoch the biblical patriarch. [...]
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link to source)
There are a lot of possibilities in which you can show your respect, gratefulness and love towards the Gods during this ritual. What I personally like to do is to directly talk to Them about this, which usually brings me tears, a lot of emotions. During that time my ideas for the ritual also come, and I do them right away, then back to conversation.
Either it's vibration of runes, mantras, saying prayers with vibration, vibrating their names.. a lot of ideas come. I don't always hear them back, sometimes these things just come as ideas in my head, but sometimes They tell me what I should do.
So you can expect to be guided to what you should do, either verbally, either through feelings or other methods, but most times not, so you should have a general idea of what you would like to do, from these ideas and also what others will suggest you. Hope this helps.