It’s a pretty typical thing in soccer to describe a player as “in form.” Consistent performance is something that people value from players regardless of the level. The markers for form vary from position to position and league to league. Despite the fact there is variation, people know when a player is in form.
Most of us are never going to play professionally, so the idea of being in form is largely irrelevant. The more important factor in most of our lives would be the concept of being “true to form.” In my mind; this is the idea of showing up the same way over and over again. People know what to expect from you before you get there. This may fly in the face of being your “authentic self”. However, the idea of being whomever you want at any given moment is unrealistic anyway. It is far more powerful to be a person that people know and understand. Be true to form.

The final piece to this that I’d like to add is keep improving your form. Incrementally get better over time in whatever matters to you. Consistency is a valuable characteristic but who you are today should never be the goal. People love you exactly as you are but sometimes that’s problematic. You are not a finished article! Keep developing the person that you are into better and better versions. Use the years of your life like the codes to a computer program. Excel 2.1 should be better than 2.0. Different to say the least but hopefully better in many ways.
Stay true to form but keep that form improving!
Pete