I’m developing a book on creativity, currently, with tutorials and demos on ideation, and personal voice development. I will cover a lot of these questions through my Legendeer Workshop, as well.
In short, you need to frame your search in terms of a question, or a riddle, if that better suits. You will not “discover” your personal voice simply by painting more, or waiting for the materials to reveal something to you. You need to be seeking something very specific, that equates to a marriage of two or more disconnected things. Start simply and try to marry two techniques, materials, themes, ideas, etc. This will relate directly to your technical process only. Other fundamental elements of design, content, color, etc. will all require there own process, but in the beginning, simply focus on one consistent subject matter, and dismiss all of the other formal elements. These are studies in which you are trying to frame your preferences, and develop something of distinction in your work. While the individual components need not be original, the final outcome should be authentic, as it is infused with your intent, your choices, preferences, and most importantly, your experiences. This will take some time, and multiple pieces, but after quite a bit of trial and error, you will find an exciting way to marry these two seemingly disparate elements, and you will have answered the original question that you made with the inquiry of your work.
Relate this to the Scientific method, and it may become more clear.
All the best,
Legendeer. Live to tell the story.
WISE words from Sterling Hundley, a friend and mentor.