DON'T just click the "Connect" button. This is a wasted opportunity.
Instead, take a little time to personalise your message. Click on the little pen icon next to the +Connect button and create a short but compelling message about why you want to connect.
Write a heading, eg "We met last night at XXX meeting" then compose a short message about what you have in common and why you'd like to connect.
If you can't connect because you don't know their email or you haven't done business with them before, check out the groups that you have in common and use one of those as a basis for connection.
If you want to get more mileage out of LinkedIn and you genuinely want to connect, then take a little time to make your message request personal and to make yourself more memorable.
Professional CV Writer, Career Coach and LinkedIn Profile Creator