JLS supports AND, OR, NOT, NAND, NOR, and XOR gates, tri-state buffers, and signal delays. All are created in basically the same way. Click on the appropriate icon on the tool bar, or right click when the mouse is in an empty area of the circuit drawing area, select "elements" from the pop-up menu, and then select the appropriate icon. A dialog box will appear in which various parameters of the gate can be specified.
Most gates support multiple inputs (e.g., a three input AND gate). Type the desired number of inputs in the "Inputs" field, or use a pop-up keypad to click in the number.
All gates can be specified as a single gate, with each input being a single wire. Multiple gates, with each input being a bundle of wires, can also be specified by typing or keying the desired number of wires each input bundle in the "Gates (bits)" field.
Most gates can point in any of four directions: up, down, left or right. Pointing right (the default) means that the output of the gate is to the right of the gate. Select the orientation of the gate you are creating by clicking on the appropriately labelled button.
The characteristics of most new gate types can be copied from the previously created gate of the same type by clicking on the Repeat Previous type Gate button.
To finish the dialog and place the newly created gate, click on the OK button. Then move the mouse to position the gate where you want it in the circuit and left click to fix it in that position (it can be moved later, so don't have to be in exactly the right spot).
If you change your mind and decide you don't want a gate of the type you are currently creating, click on the Cancel button in the dialog. If you have already clicked on the OK button but have not yet fixed the place of the new gate, you can still cancel the gate by right clicking the mouse.