Mail goes through a processing center, digitized and sent to my tablet. Make sure to include your contact information in the letter:

Texas Department of Criminal Justice 
Brianna York TDCJ# 02600551
P.O. Box 660400
Dallas, TX 75266-0400

Do not send cash, personal checks or stamps. The letter(s) inside must be addressed to the inmate on the envelope.
Mail must have a return address (as defined by the USPS ), including an identifiable last name.