Here's what I use to Pop my Moonwell Chalice, Demon Soul, and Metamorphosis (and my Immo Aura, with one button). Here's what the macro does, on the first press you will simultaneously pop your Moonwell Chalice (provided it's located in slot 14) and demon soul, the second macro press will pop metamorphosis (you want a slight delay between these two...testing has shown that chaining them w/o the castsequence results in a metamorphosis that doesn't benefit from the mastery of moonwell chalice) and the third press will pop your immolation aura. If metamorphosis is up, holding down the alt key and pressing the macro button will result in demon leap. So in total, you've got 5 abilities bound to the single button.

#showtooltip [stance:2, mod:alt] Demon Leap; [stance:2] Immolation Aura; [nostance] Metamorphosis
/castsequence [stance:2, mod:alt] Demon Leap; [stance:2] Immolation Aura; [nostance] reset=20/combat 14, Metamorphosis
/cast Demon Soul

And this one for pet switching mid fight. (If you're not farmiliar with macro-ese this macro does the following: When you have no pet out, probably after a wipe you'll summon your felguard, if your felguard is out pressing this macro button will automatically cast a soulburn and then your felhunter with one press, if your felhunter is out this macro will hardcast a felguard...this allows you to demon soul: Felguard midfight while still mostly playing with your felhunter...the optimal playstyle.)

#showtooltip [pet:Felguard] Summon Felhunter; Summon Felguard
/cast [pet:Felguard] Soulburn
/cast [pet:Felguard] Summon Felhunter
/cast [pet:Felhunter] Summon Felguard
/cast [nopet] Summon Felguard
/script UIErrorsFrame:Clear();

Finally, I've been getting questions about how to do this demo thing for people with warlock alts.

1. Do the dailies and get your Moonwell Chalice. It's the BiS trinket.

2. Never think that you're waiting too long to pop your metamorphosis or trinket/DS. You ALWAYS stack them up.

3. Always pet switch before demon soul. Yes, it's a long cast. If you're timing it correctly, you're only losing 2 shadowbolts worth of damage and the value of the Demon Soul: Felguard is about 4x the damage of a Demon Soul: Felhunter.

4. Using your pot with heroism is not worth it. Use your pot with your CD popping.

5. If you've managed to get an unempowered Bane of Doom up, reapply it after you've popped your CDs. The reason BoD is so good is because half of the time it's juiced by Metamorphosis/MWC/DS. Also, be careful not to refresh BoD until AFTER a juiced BoD has expired...you don't want to lose your last juiced BoD tick.

6. Profit.