One way that it is easy to be kind is in a crowd. Unfortunately, when people are in crowds, they tend to be stressed in some way or another which makes it difficult to remember just how easy that kindness can be. Don't you feel great if your toddler is crying loudly at the store and a random stranger gives you a kind smile? Doesn't it feel good to be let ahead of someone in line when you are in a hurry or to be instantly forgiven with a grin and a "no problem" when you literally run into someone coming around the corner. How about if the tall guy at the concert lets you stand in front of him so you can see?
How can you be kind when you are probably stressed too? First of all, if you are feeling less than kind towards someone, change your story. That lady who barged in front of you when you were looking at the lettuce? Maybe she is legally blind and could hardly see you and needed to be extra close to the produce herself so that she could make her selection. Maybe she is in a hurry because she is late and her babysitter needs to get home to her own kids. Maybe she has her mind elsewhere because she just had a death in the family. In general, people are not out to get you! Give them the benefit of doubt, and smile their way. You would be surprised how many grouchy people will relax and smile back if you bless them with a big grin. This is also an excellent tool if you feel you have made a faux pas. If you bang carts in the grocery store, smile and say your sorry. If you think you jumped the line at the bank when the other guy really might have been there first, smile and say, "Oops, I didn't see you. You go right ahead."
Don't forget about treating your loved ones with kindness in a crowd too. I have seen mothers who are incredible nice to strangers, but who scream at their children simply for not acting in the narrow way that the mother deems correct. Again, change your story. First is your kid really doing something wrong? Maybe he or she is just being himself. Second is your kid hungry or thirsty or bored or tired? How can you remedy the situation? Remember, chances are he or she didn't have much of a choice about coming along, and even if he did, he probably can't decide when you will leave. Treat your partners and friends with kindness too. Remember that you can't control others, but you can keep a joyful attitude yourself and strive to share it with everyone you meet.