You discuss size, the look your going for, you try on implants, you discuss the things that can happen during the procedure, he measures you, he advises you what size he thinks would suit you or the look your going for, you can ask him any questions, you can discuss the types/makes of implants and choose an upgrade, discuss implant over the muscle or under the muscle.
Possibly take along pics of the look your going for or try to describe the look and size so he knows exactly what you want. That way he can find the implant and discuss the options available that best suit you.

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