The first step is to know what your backpack size is? 50 Liters, 60 Liters? This is important because it can tell you how much you can actually pack in your backpack. 50-55 Liters maybe big enough for a 3 day 3 night backpacking trip. So packing for a 3 day, will be much different then backpacking for a week on the Appalachian Trail.
Before loading the pack with your backpacking gear, be sure that you have the proper pack size to fit the gear you plan to bring. In short, you want to find the line between eliminated unnecessary weight and certain luxuries for comfort. Upgrading to new and lighter equipment will help keep weight and pack size down. Also, keep in mind that shorter trips will require you to pack less gear while more gear, such as clothes and food, are needed for longer trips.
While many backpackers just throw their gear into their packs with no organization the day before their trip, there is a method in packing it properly to improve their overall backpacking experience.
Learning to organize your gear properly before loading your backpack will eliminate forgotten items and help you remove unnecessary luxuries. In addition, efficiently packing your backpack will give you more comfort, convenience and stability.
What size is your pack? And how long you will be on the trail is crucial to learning how to pack your pack.