You couldn't make it up really..... how did Suzuki do it?
Mother-tongue method. Started them really young - and assuming ours were taught according to Suzuki's principles, and I have every reason to believe they were, LOTS of listening, mostly with little music games to begin with and physical games. In our first lesson they were given a large piece of paper, the teacher drew around their feet after having put them into a good posture, told us they had to colour them in and practise standing on the paper every day and by the next week we were playing games to see if they could get it right with their eyes closed. They didn't have violins to begin with: we were told to get a smallish food-box, like a small cereal packet, and tape a ruler to it, and the practised holding it on their shoulders, spinning it around, seeing who could hold it longest without it falllng on the floor... by about the third week the teacher had given us a length of dowel and they practised games with fingers holding it.
Meanwhile we got going on the "set" rhythms - most people made up their own words to them, but ours were Everybody Down-up, Caterpillar caterpillar, Run rabbit run rabbit and Twopence and threepence - and they clapped them recognised them when clapped, heard them played on the violin, moved the dowel up and down to the rhythms, and left to right... after about a month, two little violins were hired, and they had fun practising holding them under the arm, then at arm's length and turning them over, looking along their left shoulder (head moved by the teacher: "that's what noses are for!") and lift chin back on to the chin-rest, and if a parent was there to catch it, trying to hold it there with no hands while standing with a straight back. Eventually, with gold tape marking the edges of the usable length of the bow, and with a "traffic warden" made of a pencil and a rubber band sitting against the left edge of the violin to prevent the bow sliding out of line, they played Everybody-down-up on the E string. No further than that until they were keeping the bow flat, straight and within the gold tapes. Still holding the shoulder of the violin at that stage.
But of course you can play Everybody-down-up over and over again while your teacher changes the pitches on her violin to those of Twinkle Twinkle Little Star so that you take a full part in the first of the Twinkle variations. Maybe try another rhythm: remember they've been moving the dowel "bow" - and their own bow when they got it - to these rhythms at various angles before applying it to the violin - and after another couple of weeks, listening to the teacher playing it on the A string and seeing if they can spot which it is, and then trying it on their own A string.
Fingers on the string might take about a term.
THAT is teeny-weeny achievable targets. And by exploring the ways to develop it through games and exercises, posture was established right at the start so that they know no other, correct bow-hold, straight lines - our fees included group lessons about once a month in which some of them got to play solo, some got to choose what the group would play (there were four classes - ours was the largest group outside of London) and there were a lot of simple games and exercises - I remember us having to close our eyes and point if we heard any sounds as the children picked up their violins from the floor and put them on their shoulders and then at a signal from the teacher reversed the process. Teeny-weeny steps each achievable before moving on.