When packing, make sure to concentrate the weight on your hips, so as to avoid lifting heavy weight on your shoulders and back. When trekking along hilly areas, the burden should be on the topmost part of your back, in order for the majority of the weight to fall on your hips: sleeping bag, mat, and clothing (from top to bottom).
The back seats are the noisiest, as they are usually close to the engines, while those located near the lavatories are just as noisy and it is the busiest sector of the plane. The seats on the aisles are quieter than those next to the windows, and they will allow you to get up without having to bother the passengers in your row.
In many cases, the airports in the different cities and destinations in Portugal may be far from the downtown area or from the hotel or lodging you booked. Make sure to check in advance the distance from the airport in Portugal to the hotel.
If you're traveling for a few days in Portugal, be sure to keep all important information on your email account, in case you lose your documents.