You find the instructions which are needed most frequently on the toolbar which will appear if the representation of the current block is ‘FBD’. If this bar does not appear you might click with the right mouse button on the grey pane next to the existing symbols and select ‘FBD’ out of the appearing context menu.
There will be further instructions if you click the symbol 
.
For some instructions short keys are existing:
F2 And-Box
F3 Or-Box
F8 New Connection
F9 Negation on/off
If the network is still empty you do not have to note the position of the cursor. But if function blocks already exist you will have to position the cursor onto an operand or onto the connection between two function blocks before inserting new elements.
You open the editing field of the operands by the insert-key or by entering a letter, a number, ‘#’ or the double inverted commas. After having inserted you close the field with the enter key, or, if you do not want to take over your insert you will press the ESC-key.
You can take over operands directly out of the machine. For this mark the element in the graphic window, in the address table or in the element tree. With operands which still start with a ‘?’ ( or which are completely empty) a click with the left mouse button is enough to insert the operand out of the machine. If you want to replace an already addressed operand you will have to select the last point out of the context menu.
You do not have to address the operands immediately as long as they start with a ‘?’. But as soon as you transfer the program into the PLC all obligatory operands have to be specified.
Parts of the network can be deleted by the Del-key.
By clicking right you get the context menu.
You open a block with a double click.
See also: