[header] How to travel when flying on a plane [title] Determine whether you need just a carry-on item or if you also need a checked bag. [step] Depending on how long you will be traveling or what types of items you are packing, figure out what types of luggage you need to use. [substeps] The permitted size of carry-on bags varies from airline to airline. 
Check the requirements for the airline with which you will travel to learn how big your carry-on bag can be. Remember that certain items are only permissible when packed in a checked bag.