Although strategy is to some extent personal choice, here are some ideas that might be useful.
Since each Move you make in a Game has a “cost” that is you generally you want to minimize the number of Moves you make.
Since the cost of a Move depends on the current number of Hints requested. This means that you want to make a Move if you are certain about it from either the given Hints, or your knowledge about possible words that can be formed, since to move later after given more Hints are will cost more. If you are not completely sure, you might want make an informed guess since the cost of the Move will only go up. But a wrong guess might also prove costly since later expensive Moves will be needed get to a correct 4Spell.