I believe my sun is weak. Any suggestions on how to strengthen sun?

I researched little and found out that when sun is strong in your chart, you won't care about what others think about you, you'll feel energetic and will have high self esteem. Sun is linked with vitality, energy and discipline. All of which I miss. That's why I feel like my sun is weak.

Right now I am doing surya namaskar. Is there any other practical/realistic thing I can do to strengthen sun?

I am Mesha rasi, Bharani nakshatra.

Thanks!