1) Go shopping! You need to treat yourself to a tiny shopping spree once in a while. This will also help you get a new, fresh look. Maybe your ex will spot you at a restaurant with your new boyfriend, and he may or may not be jealous! :D
2) Go outside! Maybe you want to walk your dog to the park or just even around your street. This will expose you to fresh air and the beautiful scenery.
3) Hang out with friends! Maybe you and your friends could go to the frozen yogurt store or something and talk about some crushes you all have
4) Remove any memories or pictures that reminds you of your old lover. This will only make you more sad, and you will just feel miserable.
5) Smile. Smiling is your best accessory you have! Just by looking at someones smile, you know their personality as well.
Hope you found this helpful!