One word to summarise you and your dog's training - FUN!
Your dog is 5 month's old so is very capable of tracking.
Firstly let's assume your dog can already track, which is fact, so it is just harnessing this instinct which is the solution to the problem. Between the two of you it is the dog which can track and you who cannot so the dog is always right, it is the handler who needs to understand the dog and as you have the gun dog experience you are the perfect man for the job.
I start with a small track 10 feet approx., a head or hide hidden in a bush with a small trail leading up to it. Now here is the important part. You should have an action which initiates the start of the track. By this I mean a specific tracking collar, lead (placed onto the dog when the tracking begins) and command ("Find it, where is it?") that lets the dog know you are now looking for a deer. The dog does not immediately need to understand but this same action and command repeated over time that will suffice.
Ignore all the rumours about tap water ruining blood because of the chlorine. Nonsense! For the 10 foot track we are talking about you say the command to the dog, when the dog's nose hits the earth it is "good boy! Find it!". Now take him to the deer. This is a little bit of education for him. He is looking for it but you are Alpha so you find it. When you do give the dog loads of praise and since the session should only take 5 mins give him plenty of play and don't expect him to rag the skin. It is not necessary and especially Bavarians sometimes look at the skin as "job done, now I am dis-interested". But plenty and plenty of play. Let him off the lead for a bit and if he wants carry the hide for a bit. never let him be possessive though, you own the hide not him. So don't be afraid to stick your hand in between his mouth and the hide as to say this is mine, wait your turn. Makes life easier if you are reaching in to gralloch forgetting a possessive dog is standing over your freshly shot deer, especially where Chesapeakes are concerned! They can be very very possessive.
The most important thing is that when you do the next track the following few days or next day later it must not be anywhere near the hide has been dragged and that includes heading back to the house or car after the last session. Fresh ground always.
Now if you happen to be tracking and the dog is following the scent but about 5-15 feet off the scent but in the right direction this is just "wind throw". If you try and walk to fast with the dog or let the dog go too fast it can encourage wind scenting which is not the end of the world but is a great way for a dog to lose a track as a 90 degree bend can throw the dog wasting time. So don't be afraid to hold the dog back slightly to keep him steady and if the pup takes a full minute sucking in the scent of a clump of grass just let it work away as it is finding the scent so unbelievably good it can't get enough of it. Now this trait of taking ages on a clump of grass can be a bit annoying but in time this stops.
Once the dog is starting to track about 10 foot. Move the distance up. If you have a Saturday and the dog is easily doing 10 foot track jump to 30 feet. Just be patient and if the dogs is on track try and stay quiet. Let the dog work. In time when the dog is given the command and brought to the start of a trail it is 1 command and then absolute silence just letting the dog do its thing.
As we are soon coming into summer please remember this...."Where you track and how long you track can equate to success or failure of the practice session".
By this I mean if you lay a line over heather in a summer morning and decide to track at noon then you may find your dog unable to follow the line. Diphenols in heather inhibit enzyme activity. So by understanding what scent is (i.e. enzymatic breakdown of oils and organic material) you can better understand the how powerful a scent the dog is following. Diphenols stop enzymatic breakdown which is why very little grows in peat bogland. The heat of the day then causes evaporation which means scent literally disappears. So dragging a hide over pasture or a football field in the early learning phase is much more appropriate than heather. Once you can see your dog has easily got the idea of tracking then move to forest, then harder heather moorland and always mark your track. On pasture I will use a few sally rods with a bit of white insulation tape round the top. In forest a bit or red ribbon and in heather I use markers such as a fence line, rock or tree and always following from one to the other as the crow flies. I can then usually tell if the dog is following wind throw or the drag trail.
As for putting flecks of meat on the trail or ending the trail with food it is unnecessary. Tracking training is hunting and fun. Food is for dinner time at the home. Being out is the dogs reward so there is no need to mix food with tracking. There is no need to lay flecks of meat on the trail and even a dragged skin or head without any blood is perfectly fine. The dog can easily follow a hide trail so need to run to the ends of the earth looking for deer blood.
Other than that I hope this helps. I have been able to put a lot of this into practice. I have been helped along by the Scudd in the past in collecting parts for my dogs and have been able to put what I have said into real use.
I would just like to say that your dog is young, the season is drawing to a close and you have plenty of time. You find the hide the first few times but praise the dog. If the dog does not follow the first few times then it is what it is, so you find the deer hide, but give the dog the praise for it. Then after a while you will see how powerful their scenting ability really is even over marshland with water up to your knees!
Remember FUN FUN FUN and more FUN (oh and a sprinkling of patience as you wait for your dog to understand the game you are playing). Sometimes it is not the dog being trained, it is the handler.