If you expect to get wet, stow everything in polythene bags. Pack so that you know where everything is and so that the first things you need are not buried at the bottom. The sleeping bag is probably the last thing you need so that goes at the bottom. Your tent should be on the top, so should heavy kit such as radios, which are more easily carried there – though try not to make the pack too high, if you have to cope with strong winds, for a very high pack will be more difficult to balance and you will expend a lot of energy just keeping upright.
Pack a stove and brew-kit in a side pocket so that you have easy access when you halt. Make sure that foodstuffs that can be easily crushed or melted are in suitable containers. In a warm climate you can carry food to eat cold and make plenty of hot drinks. In a cold climate make sure that you have plenty of fats and sugars. The exact rations depend on your taste, but they should be chosen to give a good balance of vitamins, minerals, fats, proteins and carbohydrates. Take into account the extent to which you will be able to live off the land and carry a supply of anything unlikely to be available locally.