Like ctd57 said...It is basically like a repeat...The only real difference is, you are teaching the whole time. Verbalize EVERYTHING - pretend you are teaching a new instrument applicant. That way the DPE/FAA guy/gal will know that you know what you are doing
Stay calm, relax, and just have fun...this one is easy compared to your CFI...and your MEI will be even easier...
Good luck Sir!
Lax