A young horse's training log has two readers: you, next month, checking what to work on — and a trainer you may never meet, years from now, trying to understand the horse in front of them. Write it for the second reader: plainly, in order, with the cues and quirks included. Do that, and the horse's education survives every change of yard, rider or plan.
The session entry
After each session, write a few lines while it is fresh: the date, where you worked, what you did, and how the horse responded. 'Long-reined in the arena, first time past the jump fillers — looked hard, snorted, then went on' teaches more than 'good today' ever will. Note what was new, what was repeated from last time, and what you deliberately left alone. Record the rough length of the session and any tiredness or tension, because a young horse's difficulties are often nothing more than a session that ran long — and the log is how you spot that pattern instead of blaming the horse for it.
Milestones, dated and described
Keep a separate milestones page at the front of the log: first saddle and girth, first mounting, first steps under a rider, first loading and travelling, first hack out, first clip, first visit from the farrier with how he stood. Date each one and add a line about how it went and what helped — a calm companion horse for loading, a particular quiet lane for first hacks. Milestones are what a future trainer scans first, because they define what the horse has genuinely done, as opposed to what he has merely been around. The 'how it went' lines matter just as much: they tell the next person how to repeat each step successfully.
Cues, aids and quirks — the horse's vocabulary
The most valuable part of the log is the vocabulary. Record the exact words you use, what your rein and leg aids mean to this horse so far, how you ask for each transition, how you reward, what settles him and what winds him up. Add the handling truths: how he is to catch, whether he ties quietly, what he thinks of clippers, sprays, rugs and the vet, and anything he dislikes enough to plan around. None of this is written on the horse. Without the log it walks out of the gate with whoever trained him, and the next person pays for the same lessons twice — once in time, once in the horse's confusion.
Periodic summaries for handover
Every few months, write a short summary at the current front of the log: where the education has reached, what is established, what is still fragile, and what the next stage should be and why. If the horse is sold, loaned or sent away to be produced, that summary, with the milestones page, lets a competent professional continue the same programme from the first week instead of spending a month discovering the horse by trial and error. Send the whole log with him — keep copies for yourself, but let the record travel — because a horse's history is part of the horse.
That handover is exactly what KinsLe's Transferrable Profiles are built for: the profile moves with the horse, its history, records and routines intact, so a youngster's training story reaches the next trainer whole rather than retold.