Simple enough achievement, but here's a few tips.
1. Use a helper like
http://www.scrabulizer.com/ to maximize tile use.
2. Don't leave yourself with tough letters when it gets to the end. Swap letters like V, G, K, etc. that are hard to use before the tile bag is empty.
3. Ask the person you are playing if they'll let you place all your tiles. The community is nice, and this worked for me.
This is a fairly easy achievement that just requires some planning and strategy.
Good Luck!