When creating the Lacy Beginnings Scarf , I kept getting nervous about the edges. They were quite wobbly looking. Tension was definitely the culprit. I was using big needles and very fine yarn. When using these complete opposites, it is hard to keep an even tension, especially at the edges.
My anxiety was calmed after I did a quick internet search as to the best way to get my edges in check. Here is what I did:
1) Wet Blocking: Sometimes (like my project) you just need to wet block your piece correctly. Take the time to secure your work with pins or clips and stretch the piece so that everything is nice and even. Repeat the process if necessary
2) Slip the first stitch (S1): Slipping the first stitch creates a smooth a stitch pattern along the edge of your work. Just make sure you are slipping purlwise. Need help with how-to slip those edges? Click here for a great video.
3) Tension: Even tension is a learned skill. Basically I encourage others to just keep knitting. However, when I reach the last stitch I give it an extra tug (a light tug) to keep it as tight as the other stitch.
So how do you keep your edges in line?
knitsbywhit 
Definitely blocking. I try to keep that loose first stitch in check, but sometimes it does what it wants anyway. Blocking whips it back into shape. 🙂
Edges can be so tricky. Ugh.