Wave master control

Guide for each mini:

Wave master
The wave master is a powerful hero even in lower levels. When playing wave master you want him to be placed behind or near the golden giant and mini pekka should be behind them. You just need to place all your minis on the board as quickly as possible to maximize support on dps for the wave master.

Golden giant
As your main tank, put it at the front to soak up as much damage as possible, dont put it down in front of a pekka or any non stunner minis that have a lot of damage. It's best to unlock the second star upgrade rather than the first in case your opponent uses mini pekka which is very often as he is the meta in countering tanks and other heroes.

Mini pekka
Your mini tank or dps, because of this your goal is to put him near a hero or tank to eliminate them. Mini pekka often dies most of the time to other high damage dealing minis so it's best to have him eliminate as many minis as possible before that and with the help of bowler and spear goblin, it will be quite annoying to deal with.

Spear goblin and bowler
You always want them a tile or two next to each other to maximize control over the board. Get the spear goblin upgraded for the damage and the stun ( or after the update attack speed boost ).

Fisherman
Not much to say other than use it on the important tiles to prevent opponents from using it and never get the upgrades unless your very confident with your luck or prediction skill. Best to get after the second or third round and play your spear goblin and bowler only so the opponent doesn't expect the fisherman pull.