I was 23 yo at that time. If I didn't try, my T levels were around 700 back then. I don't remember the whole protocol but the main things that I remember:
1. High saturated fats (grass fed), lots of eggs (12+ a day)
2. 9+ hours of sleeping (blackout curtains, cold room, no phones in a bedroom)
3. High quality multivitamins (zinc, boron, magnesium, D3, selenium were my priorities). Also some pine pollen tea, Fadogia Agrestis, Tongat Ali etc.
4. High protein diet, calorie surplus
5. Cold showers
6. I even remember putting Lugol's iodine on my balls, not sure how it helped, haha
Also at that time I was single and went to multiple dates. That could play a big role too.