Before generating the Gerber you need ensure the setup is appropriate.
go to File>>Fabrication Outputs>>Gerber Files
2) General Tab
In general option set the precision to 2:5 as shown below:
3) Layers Tab
In order to manufacture the PCB you need different layers.
Please ensure you have clearly defined outline in the mechanical layer.
For the 2-layer board , there will be no inner layers (G1,G2......).
For the 4-layer and 6-layer board you need to include inner layers as per the design.
Include all the layers by selecting the required layers in the plot section. In the mirror section ensure that none of the options are selected as shown in image below:
4) Aperture Tab
Since the Gerber files require Embeded apertures you can select the Embedded apertures ( RS274X ) under the Apertures option as shown in the image:
5) Advanced Tab
Kindly ensure all the configurations are fine.
Click OK button to generate gerber files.
6) Exporting Drills
You need to Generate the drills in excellon format
go to File>>Fabrication Outputs>> NC Drill Files
We highly recommend to choose the same units and format parameters as the Gerber as shown in the image below:
Then click OK to export drill file.
Now we have all the files required for the PCB fabrication. Kindly put them into a single zip/rar file.
Upload the zip/rar file to www.lioncircuits.com
Here is the step by step Order Guide