Self-control is so important Paul requires it of each group he addresses in Titus 2. It is the only virtue for all four groups, the only virtue for the younger men. However, Paul himself says, "I have the desire to do what is right, but not the ability to carry it out. I don't do the good I want, but the evil I don't want is what I keep on doing." No self-control Paul.
But Paul makes a point. This is not your self-help kind of self-control. A dictionary definition will simply lead to discouragement, failure, and disappointment. Jesus says, "Apart from me you can do nothing." So it goes with self-control, nothing self-made about it. If Scripture requires self-control from every Christian, then self-control is attainable by every Christian. Take courage! Where God guides, God provides!
For brevity and simplicity, self-control in Titus 2 is to be wise and prudent in nature. How do I get self-control/wisdom: Proverbs 9:10... the fear of the LORD is the beginning of wisdom. What is the fear of the LORD: Proverbs 2.
SELF-CONTROL = WISE = KNOWLEDGE OF THE HOLY ONE = WALL OF PROTECTION
"Discretion (self-control) will protect you and understanding will guard you" Proverbs 2:11. Self-control is not simply ceasing to feed the flesh, it is beginning to feed the mind. Feeding the mind with knowledge of Him, His character, His Word. Then, wisdom will enter your heart, knowledge will be pleasant to the soul. Scripture will not be laws, rules with burdens, but a beautiful boundary. A wall of protection, welcome and necessary.