If you want to do precise, fast, and fine pitch SMT assembly, you'll have to switch from 'wire' solder to 'paste' solder
Wire solder is what most people start with, it comes on a roll:
When doing SMT work, you can use thin wire but often times even that isn't good enough, you need to use paste! Paste comes in tubs of 1/2 - 1 lb or so. The paste has consistancy of smooth peanut butter and is made of ball of solder suspended in flux. As the paste is heated in an oven the solder melts and the flux burns away leaving a solid solder joint.
We may have a future tutorial with more details about choosing paste and solder but for now we will move on to what this tutorial is about which is how to store solder paste.
The problem with paste is that the flux can evaporate off, leaving the paste 'old' and 'dry'. It won't screenprint as well - you'll have difficulty with bridges and getting clean deposits. Paste should be kept cold, but not freezing. Kester suggests 0-10 degrees C (32-50 degrees F).
If you can get your hands on a cube fridge, we suggest using that - make sure that no food is stored in there as paste is toxic and it gets everywhere. If you don't have space for a cube fridge (like us) here are two solutions we found.
We picked up this fridge from thinkgeek, but you can find 12V camping fridges at most appliance stores. It draws about 60W and has a temp display on the front. It tends to keep stuff inside at 45 degrees F or so which is perfect for us.
One thing to watch for with these is that they condense water during the summer months so you may want to keep a rag on the bottom to soak up water and wring it out once in a while.