The one who is full of love is the one who is always happy.
When you are constantly having love for everyone, you'll have no negativity. Your unselfish love will make you have only positive thoughts and you'll find yourself in constant happiness. Start your day with thinking of all the people you come into contact with. Then take a thought in your mind that you have love for all of them. This thought will help you throughout the day. You'll find yourself accepting others as they are and having good wishes for them.