If invoice printout does not show GST Separately in column,you can follow given steps:
Step 1:Go to The administration menu,
Step 2:Click configuration,
Step 3:Click invoice/Document printing,
Step 4:Click standard,
Step 5:Select sale invoice,
Step 6:In the Body column click self configured,here you can increase the width of GST column as CGST,SGST,IGST according to the total width,total width should be 136 only.
Now save this window,and GST will be shown serprately in column on your invoice printout.