One way to counter Shaco that has always worked for me:
i choose a tanky jungler with lots of cc--malph, naut, mao
invade with 4 teamates into his blue at the start-- he'll need that to jungle quickly and well
have the last teammate( top if blue team, support if purple team) guard your blue and check for another counter jungle
Come up through the curved brush near mid and go through by wolves then jump him--- since he puts his boxes in the corner he wont have any defense-- focus him first then any others u can kill (CV WILL HELP A LOT)
usually you should win the fight and just take his blue leaving no minigolems
consistently go back whenever the camp respawns( u have to time it- blue and red respawn every 5 minutes) on the same route with a ward if possible and try to steal it by timing to use your smite when he's fighting it or if hes gone
IF SHACO IS COUNTER JUNGLING, get lots of wards( sight is the ultimate advantage) and be ready to get to your red/blue whenever it respawns try to get it and/or wait in the bush near them and steal it then kill him
it can be risky, so if possible have a teammate with you
but unfortunately if shaco is fed or very farmed/ doing well, then he usually can't be stopped-- as with many other champions such as trynd, akali, noc, udyr, gp, etc.-- so just surrender or do what you want, but you will probably lose-- therefore, the best counter to shaco is to stop him from starting because this is shaco's weakest point, at level 1- he is extremely squishy and with the help of teammates you can kill him easily-- TRY TO CATCH HIM OFF GUARD