[This is NOT a guide, just a helpful tip]
A very easy way to nab this achievement (along with Wild Card obviously)
If you have done the main story and followed Mr. House to the end, thus getting 'The House Always Wins' and 'All or Nothing,' AND if you have a game save just prior to accepting the final quest at Hoover Dam (when you talk to Mr. House and a large warning message pops up asking if you are really ready for the endgame), you have saved yourself a ton of time.
Reload this save, and just go kill Mr. House (use the terminal to the left of his big screen). Assuming you have done everything correctly for the Mr. House quest line up until this point, that being:
-Get Platinum Chip
-Upgrade the Securitron army under Fortification Hill
-Meet and deal with all factions i.e. [The Brotherhood of Steel, The Great Khans, The Boomers, The White Glove Society, and The Omertas]
-Save the NCR president
-Trip the switching station switch
which I'm assuming you'd have to do to get the endgame question anyways, all you need to do is talk to Yes Man and get him installed onto the Lucky 38 computer. From here, you essentially do the same exact endgame sequence of events as you did for your play through of 'The House Always Wins,' with limited change in dialogue.
Enjoy the easy cheevos!
###Also as a note, you can essentially come back a do the Yes Man ending from ANY of the other factions, but depending on which one, you may have a few more quests before the endgame sequence.
For extra help with any of this quest, go to this website:http://fallout.wikia.com/wiki/Fallout:_New_Vegas_walkthrough
All credit for the link goes to fallout.wikia.com and its supporters. The site is amazing; it helped me a ton for Fallout 3. Just click the Vault Bottle Cap logo on the top left for the Fallout 3 stuff too!
***If need be, go read a solution (like the others on this page) for exact methodology to beat the quest. Since your this far I'm sure you can beat it anyways, so I'll save myself the typing...