Since my most recent post about the six questions an actor should ask themselves when taking on a role, I have gotten many questions about how I actually portray my characters in a show. And to answer that question, I use a technique called, "substitution".
The definition of substitution is: the action of replacing someone or something with another person or thing. Using this definition, we can use substitution and apply it to the world of theatre. Substitution (theatrical), is the understanding of elements in the life of one's character by comparing them to elements in one's own life.
Basically, substitution is using your personal life, experiences, and emotions, and applying them to your character.
For instance, let's say your character is dumped after a long relationship. If you have never experienced heartbreak, it might be hard to portray someone that has. But if you have experienced heartbreak, you can use substitution to apply your feelings and experience of heartbreak to influence your character's experience with it. This not only gives you a way to connect with your character, but also provides an easier way to relate to them.
However, there are some limits. As an actor, I would refrain from using substitution with any seriously traumatic events or experiences. Substitution is solely for the purpose of connecting with your character, not taking yourself to a poor mental state for the sake of a role in a show.
I hope you found this technique helpful in your acting, I personally love it because it gives me a way to relate my character and step into their shoes, without having to completely change my method of thinking.