Exercise and stay active. Activity helps promote a good night's sleep. Get at least 20 to 30 minutes of vigorous exercise daily at least five to six hours before bedtime. Avoid or limit naps. Naps can make it harder to fall asleep at night. If you can't get by without one, try to limit a nap to no more than 30 minutes and don't nap after 3 p.m. Avoid or limit caffeine and alcohol and don't use nicotine. All of these can make it harder to sleep. Avoid caffeine after lunchtime. Avoiding alcohol can help prevent restless sleep and frequent awakenings. Stick to a sleep schedule. Keep your bedtime and wake time consistent from day to day, including on weekends...once your sleep cycles regularised your erection problem may vanish... Consult nearest sleep medicine specialist they will do the needful.