Darse color (THAR-seh coh-LAWR) literally means "to give color to oneself." It is a solid expression that means "to realize the thuth of the matter." An equivalent expression is darse tinta (THAR-se TEEN-tah) which means "to give ink to oneself."
Example 1:
Estudiante: Párale, la maestra ya se dio tinta de que estás copiando.
Maestra: ¿Qué esta pasando aquí?
Student: Stop it, the teacher already realized you're copying.
Teacher: What's going on here?
Teacher: What's going on here?
Example 2:
Edecán: Este ron está super suave.
Transeúnte: Entra sin que te des color de que es licor.
Edecán: ¿Le sirvo más?
Model: This rum is really smooth.
Random dude: You can drink it without even realizing it's liquor.
Random dude: You can drink it without even realizing it's liquor.
Model: Would you care for more?