Hi sir iam 24 years old how I can make big panis

how to make big panis ? 
The male needs a penis length of 8 cm or more to complete the sexual process , If the length of the penis is 8 or more during the erection of the penis, there is no need for any intervention to enlarge the penis, as this length is sufficient to complete the sexual process, as the length of the vagina of women about 8 cm, The only way to enlarge the penis is through the operation, but the operation is performed only if ithe penis is less than 8 cm ,  , 
We also recommend exercising, losing weight in case of obesity, and stopping smoking
and if there is testosterone deficiency you can use testosterone injection as recommended 
Diagnosis :
By taking full medical history and Doing clinical examination and CBC , and Testosterone level and Ultrasound on the penis 
Causes :

• Hormonal problems 
• Obesity 
• Smocking
• Bad diet
• testecular atrophy

Advice :
you should visit the andrologist to get proper managment