I like to start a puppy tracking at 8-10 weeks of age. They cannot concentrate for long periods of time but the skills you imprint to the pup when he is this young will never be forgotten.
When I start my pups I begin with hard surface (concrete or asphalt) tracking, once they learn hard surface vegetated becomes easy. Use caution when picking your tracking area as newly laid asphalt will make your puppy/dog ill.
To start the pup I place several pieces of hotdog in a cut off section of a nylon and by stepping on the loaded nylon as the track is laid I can leave enticing scent on the surface. I make my track about 10-15 steps in length stepping on the nylon each step I take. I do not age the track at all. The end of the track has a few small pieces of hotdog as a reward for the pup (do not use the ones in the nylon). I bring the pup to the start of the track and point to the track, I do not say anything at this point. When the pup gets curious about the smell and starts to follow the hotdog juice trail I will tell him to track.
As the pup moves down the track say nothing, you do not want to break the pups concentration as he follows the scent. If the pup comes off the track or gets distracted simply get his attention and point to the ground. Once the pup restarts you can give the track command again. When the puppy reaches his hotdog bits at the end of the track praise him profusely!
I will lay 4-6 of these very short tracks each session. Each track is laid fresh during the first week of training. The second week I will lay 3 tracks at a time and then start the pup. By the time he reaches track 2 and 3 they have aged a little bit and provides more of a challenge to the puppy.
When the puppy is able to follow these short tracks easily begin to lengthen the track a little at a time. I usually increase the length by 5 steps every 3 tracks. At the same time decrease the number of times you step on the loaded nylon so the pup has to move forward to find the hotdog scent. If at any time during the lengthing process or the decreased amount of hotdog scent the puppy shows confusion help the pup find the end of that track and then lay another that is a bit shorter or has more hotdog scent. Remember we are imprinting the puppy, we do not expect him to track like an adult dog.
When the puppy can track up to 25 feet in a straight line and seems confident doing so it is time to add a turn. When introducing the puppy to his first turn on hard surface you want to make the track so that is draws the puppy around the turn. I do this by laying the first leg in the normal way until I get close to where I want to turn. About 3 steps before the turn I will shorten my steps so that I am not making a break between steps (shuffle stepping) and I will step on the loaded nylon with every step I take. I will make the turn a slight arc not a 90 degree as I shuffle through the turn and continue for 6-9 shuffle steps after the turn. Once I have made my turn I will place a few tiny bits of hotdog so the pup is rewarded for working out the turn. You will continue for a few normal steps and place the pups reward at this point. The leg after the turn should be very short at first. You can increase the length of the second leg as the pup gains confidence in negotiating turns.
I like to turn a different direction with each track I lay so the puppy does not get used to turning in one direction. I find that the puppy learns better when he cannot second guess which way the turn may go. When the puppy is showing confidence in a track with one turn and you have lengthened the second leg to about 25 steps it is time to add two turns in the track.
When adding the second turn you will want to shorten the overall track length. Make the first leg about 10-12 steps then make your first turn. Continue another 10 steps and make your second turn, end the track 10 steps after the second turn. It does not matter if you have a turn in both directions but do pay attention to the direction of the wind when adding the second turn. You do not want the scent from the last leg blowing towards the first leg or the puppy may cross over without running the whole track. You can make a horseshoe type track as long as the wind is moving across the track from start side to finish side. Example of wind direction for horseshoe or U shaped track: if my first and second turn goes to the left then I would want the wind moving from right to left when I start the first leg.
Once the puppy is tracking a two turn track on hard surface you can move to vegetated surface.