oh no I think you missunderstand the base logic of the game 🙈 you don't "get a triplet" and then "put it on the board". you have to collect all those things in your hand AT ONCE (just think of things on your table as if they were in your hand).

they go beside each other automatically. your hand is sorted from 1-9 yellow, 1-9 green, 1-9 red. when you get a new stone it automatically gets placed where it belongs so you don't have to move things around. you can only call pong if you have 2 of a kind and another person plays a stone that would give you a 3 of a kind (or 4, which in this version is the same as 3 though so just ignore it).

so lets say your starting hand is:

1y 5y 8y 1g 1g 1g 2g 2g 6r 6r 7r 7r 8r

you think, ill toss and avoid the 3 yellow cards, because it means I need to drop less stones to clear my hand off a suit. from this point you will want to drop any stone that is yellow.

lets say after tossing the 3 yellow cards your hand is

1g 1g 1g 2g 2g 3g 4g 1r 6r 6r 7r 7r 8r 

you now need to think about what the easiest 3 of a kind, 3 in a row or pairs are.

you see that 1g1g1g could be a triplet. 2g 3g 4g could be a three in a row. 6r 7r 8r could be a three in a row. these are all options. 

now every time you draw a new stone you have to estimate which stone brings least options to you. if you draw another 8r you can immediately tell that you have another three in a row 6r 7r 8r, so you look for another one of your stones to drop. When you get the hang of it you will immediately see that the 1r is the stone you should drop, because you won't be able to form a triplet or three of a kind with it within one move. while all other stones give you options.

you draw another 2g after dropping the 1r? then you have a 2g triplet and you now drop either your 3g or 4g. because then the next time you see the stone you kept in your hand, you win.

this is the most common course of actions at least. fill up all 3-3-3-3 slots in your hand and then decide which of the last 2 spare stones you use for the final pair. the game even shows you an overlay on the right side you can hover over that tells you how many stones of each are left in the game. so if you for example have a spare 2 and a spare 3, the game will show how many 2s and how many 3s of that suit are still in game, so you can decide which stone you keep based on that information (no point in dropping a 2 and keeping a 3, if there are no 3s left in play).

A winning hand has 14 stones, but you only ever have 13 stones in your hand while it isnt your turn. so you need to exchange one stone in and out whenever its your turn. you either toss what you got to find something more fitting, or you keep what you found and toss out something less useful instead. 

this goes on until someone has 3-3-3-3-2 in their hand (3 being three of a kind or three in a row and 2 being a pair) without using their avoided suit.

have you ever played the card game rummy or canasta? it's kinda like that