The first section you will see is called Payload Stations. These stations are read in real-time from the loaded FS aircraft and these are usually set via the aircraft's aircraft.cfg file. Whatever is listed in this file, gets shown in this section. Here you will be able to move the sliders around until your total payload figure matches the required payload amount. Both of these figures will be shown on the next picture.
In blue, you will see what the loadsheet determined your required payload for this flight is going to be. It is based on the flight's required fuel amount, route and whether it's a passenger or cargo-only flight. The amount listed as required payload, is the amount you need to set via the sliders and will be shown under the Payload To Be Loaded label.
As you move the sliders around, the Payload To Be Loaded amount will be update in real-time in order to show you where you sand with your payload figures. Once this figure matches the required payload amount, the Load Payload Into Aircraft button will become active and you will be able to click on it to commence with the payload loading process.
You also have the ability to print a hardcopy of the generated loadsheet which will be shown in the next figure.
The loadsheet is based on an actual real-life loadsheet used by an airline. It will show all weights regarding fuel on board as well as cargo weights among other things. If it's a passenger flight, it will itemized stuff such as the amount of passengers on the flight and how much weight in total when you add 170lbs per passenger, plus 20lbs of carry on weight and 30lbs of checked luggage (50lbs if it's a "heavy" aircraft).
If it's a cargo flight (such as UPS, FedEX, etc), it will not have a passenger figure, but a total cargo weight figure. Whatever the total payload figure is, this is the amount that needs to be loaded into the aircraft via the payload sliders.
LD will determine whether it's a cargo flight, not by the airline chosen but by the aircraft. If you look closely at the aircraft dropdown list, there are 2 sections. One is for passenger aircrafts and the other is for freighter aircrafts. When flying a cargo flight, make sure the aircraft you choose is one listed under the freighter aircrafts section. Otherwise LD will generate a passenger load instead of a cargo load.
The loadsheet is very straightforward and self explanatory. After going over it, you will be able to see how everything adds up and coincides with the previous Trip Folder and fuel load assignments.