At first glance both words seem to mean different things, but when looking at how people use the word in society today and their lexicon, both words appear to be the same.
Kelsey had a good technique/strategy at drawing watercolour drawings.
A cancer support charity raised £35,000 for charity due to its strategy/technique of running charity races in scenic locations.
A singer relatively unknown to the music industry was asked for an interview, so given that she creates media and appears in the media, she was very careful to have a good strategy/technique for how she conducted herself in the interview, what she said and how she said it.
From the above three examples, it appears that both words can be used interchangeably. So if it can be, and people do, what's the difference?
a particular way of doing something, especially one in which you have to learn special skills [source]
A technique is a particular method of doing an activity, usually a method that involves practical skills. [source]
the process of planning something or putting a plan into operation a plan that is intended to achieve a particular purpose [source]
A strategy is a general plan or set of plans intended to achieve something, especially over a long period. Strategy is the art of planning the best way to gain an advantage or achieve success, especially in war. [source]