Bicycles are awkward things to carry. You usually have to hold onto the top tube, or on the seat tube, and neither position is very comfortable. If you have a need to carry a bicycle up stairs, or over an obstacle, or onto public transport, and do any of those things frequently, you might want to check out this Kickstarter project:
Designed for urban commuters, this minimalist handle makes carrying your bike actually feel easier and lighter by lowering the center of gravity and using your normal muscle groups for lifting and holding your bicycle, same as lifting a grocery bag or carrying a briefcase. Because it’s easier to lift and hold, you’re in more control of your bicycle, making it safer to hold in crowded settings.