Think of it as a good experiment....
Try this: Run a chain until you think it is ready to change, or remeber how long you ran. Then, at HALF that time, try filing the chain. See how much difference it makes. Then run half that time again, (1/4 of what you would have run it) and file it. Notice the diffeerence. You will quickly be able to sense the difference between worn and fresh in a tank or two. (I have longer chains and small gas tanks, so why I reference one or two tanks. depends on the wood also and chisel or chipper chain. goose does one tank, and he uses full chisel.)
Plenty of good info on AS site, but I think you will get overwhelmed about the 'ultimate' suggestions. For now, just start with learning to make it sharper than it is now! Doesn't have to be perfect on a few tries.
I would NOT free file it, use a guide. Touching up later without a guide is possible, but learn with a guide for now. It is important to have the file correct diameter located at the right height. This is what sets the angle of the top plate. File too low, the top plate angle is too shallow.
There are small roller guides that you hold on the chain and run the file across it. I have not used.
IMO the ones that clamp on to the bar are too time consuming and complicated to use. Had one, gave it away. I find hand filing almost as good, and the clamp on ones don't replace occasional grinding anyway.
I use the guide that clamps onto the file.
http://www.stihlusa.com/chainsaws/acc_filing.html#filingkit
Middle of the page.
You do need to get the guide and file diameter size for the chain you have. Assuming you are using rounded corner chipper/semi chisel chain, not square cornered full chisel?
Get several plastic file handles also. An old tubeless tire rubber stem works in a pinch, but don't file without some sort of end handle. Running a file pointed end through your hand would ruin the day...
Raker depth gauge and flat file are top right of the page.
Half dozen rounds, flat, depth gauge, and file guide would probably less than $25.
STihl has some simple info in the video (avialble on their site). Oregon and CArlton sites have better info.
I have a clamping thing on top of my saw tub, but try clamping the bar between a couple boards in a bench vise. You want it rigid, not wiggle or it rounds the cutting edge. ONce you learn, you can file on teh tailgate or on a log,but for now reduce the number of variable.
I set the brake, mark one tooth with white paint marker stick to know where I started. If you have a painted master link already start there.
File from inside to outside. out to in the sharp corner is harder on the file.
Align file with the tooth angle and note which stamped line of the file guide linges up (different marks). Worry about changing the angles later, just duplicate what you have for now.
Handle flat, 90degrees to bar.
Look at the edge of the inside plate, not the top plate. File several strokes until it appears sharp. Don't worry about finding the worst, 'master tooth' for now. Now do all the teeth that way.
File a few RH teeth, then the LH teeth, then release chain brake, move chain ahead, reset, and file some more.
Depth guages, STihl shows using the tool over the teeth and flat filing the gauge down flush with the tool. I was taught to use the tool, slide the end of flat file across the top and if it snags the tip of depth gauge, it needs lowering. Don't file as is. Lift the tool and stand it on end in the notch ahead of the cutter, behind the dg (in the space you filed with the round file), then flat file the dg. The tool acts as a prtector for the newly filed tooth. One slip of the flat file would take off your newly fresh cutter edge otherwise.
It may take you a half hour first. In normal work, it is less than 5 minutes.
This is abreviated, I'm sure I missed plenty. check CArlton and Oregon sites. I need to head to work. goose, over to you.
k