Put the decoy in the right environment. For example in shallow water for ducks or on a field for geese.
Use a decoy of the same type of animal that you want to attract, sometimes however it could be good to use a decoy that the animal you want to attract eats, a rabbit to catch a fox.
You don’t have to care about which direction the decoy is looking at.
If you have many decoys of the same type it’s really good to deploy them next to each other, it looks more real for the animal that you want to attract.
If there is much decoys in an area the real animals feels much safer and put their guard down “if all these other animals are here it must be safe from hunters and other dangerous animals”.
When other animals try to engage with the decoys and nothing happens the animals don’t get scared away, in fact they often become more curious and stay around longer.
In some areas there is a limit of number of decoys (usually 200 decoys)
Its’ important that you remember all your decoys, it’s not uncommon that hunters shoot their own decoys and a good decoy isn’t cheap so try to avoid this. The best way of avoiding it is to have a map of the area and mark all the spots for decoys.
A decoy made in plastics could be out in the wilderness all year. It’s however really hard to remember where you have deployed all the decoys after a while so be careful and keep track of your decoys.
Some animals are really easy to fool with decoys and some animals are much harder to fool. For an example you can’t fool a fox with a bad decoy, you have to invest good money in a really good decoy to be able to catch a fox.