How can I cancel a connection request I already sent?

On Rolo, you can cancel connection requests if the person you want to connect with is a non-auto-accept user.

Simply just go to 'Request' on your Contacts page, type their names, and re-tap the grey 'Sent Request Contact' button so that it will change to the blue 'Add New Contact' button again. After you cancel the request, that users will no longer have a pending connection request from you.