Anticipation really can work for you or against you. It can be a positive or a negative.
It's been said that anticipation is half the pleasure of an experience. It really can be a wonderful prelude to a delightful event—bringing pleasure and enchantment before a thing really occurs and adding to the event itself.
Or it can rob you of today. It can build up your expectations way beyond what the event itself can deliver, thus ending in your disappointment.
What's the difference?
Minimize the time you spend living in the future. If you spend an inordinate amount of time thinking about upcoming events and experiences, you are likely robbing yourself of the full experience of the present. Enjoy today. Savor what you experience right now. Tomorrow you won't have that opportunity.
Keep your expectations realistic. Don't set yourself up for disappointment by thinking it'll be an absolutely perfect experience. Expecting perfection generally ends in disappointment.
Let anticipation work for you. Feel the joy of your life today. And give yourself moments to delight in what's coming. Keep a perspective and realistic balance between the two.