Watch your thoughts as you watch the street traffic. People come and go: you register without response.
This is a meditation instruction that city dwellers especially may find relevant.
If your day involves walking on city streets or taking the subway, you already know how to detach. In meditation we cultivate a similar detachment from our own thoughts.
When you sit to meditate, treat your thoughts the way you treat strangers on the subway – with dispassion and detachment. Keep bringing your awareness back to the breath or the mantra or whatever you are using to focus your attention and concentrate your awareness.