Fight the desire for comfort. The proof is that when you're full of excitement and energy, you simply can't sleep. You're not sleepy. If life is a bore, you feel more like sleeping. Someone who loves life doesn't want to go to sleep at night.
Children are a perfect example.
From the moment a baby opens his eyes, he's up like a shot. He's afraid of missing all the excitement. To capture this zest for living, you need to focus on the deeper purpose and meaning of life. Look for fascinating, fulfilling activities. You are excited.