Date yourself. Spend quality time on your own learning to enjoy your own company. Show yourself love in the way that you would show love to anyone else- through kind words of affirmation, enjoyable activities, gifts etc. Whenever you think about saying something negative to yourself imagine what you'd say to your best friend and say that instead. Unlearn all the ways that society has dictated your worth or lack of worth via productivity, wealth, body image, beauty standards, perfectionism, etc. You are truly lovable exactly the way you are.