General Use:
* Employing
* Utilizing
* Applying
* Exercising
* Wielding
* Handling
* Operating
* Manipulating
* Working with
* Making use of
* Taking advantage of
* Putting to use
With Tools or Equipment:
* Operating
* Running
* Controlling
* Mastering
* Handling
* Employing
For Specific Purposes:
* Exploiting (can have a negative connotation)
* Leveraging
* Harnessing
* Capitalizing on
* Employing (for a specific task)
Informal:
* Putting to work
* Making the most of
More formal:
* Implementing
* Deploying
* Utilizing
* Exploiting (in a neutral sense)
The best synonym to use depends on the specific context and the desired level of formality.