Take care of your health. Medical facilities will not be extensive. Get your sleep and rest. Take charge of your recovery . . . Request therapy, if available.
Most programs have waiting lists based on parole eligibility.
Show significant interest in participation. Sometimes it can help in getting enrolled. Study self-help literature. It is available by mail. Join a self-help group, such as Alcoholics Anonymous or Sexaholics Anonymous, or start one if none are available.