Non GST Registered, PAN India technical service provider / goods buyer-seller

I have started a small enterprise (like a freelancer) with 2/3 people to provide technical service and sales to the industries. My enterprise is Proprietary ship, get trade license from local Panchayet and a have company current bank account. I do provide service ( plan to sales) on all over India. I have contacts. I neither have GST registration nor applied yet. And as of now also not interested, because of return filling paper works. And my turn over will not crossed 20 Lakh on this FY. My Questions: For sale of services: 1) What type of Bill / Invoice I need to raise for my services to the registered client? What tax need to included? And what information must reflect on the invoice? For example: I had done a service to a limited company ( same state where I belong) and charged Rs 5000.00/- . They sent PO of 5000.00/- + 900.00 (9% SGST + 9%CGST) =5900.00 . Because I mentioned Taxes will be extra and on clients account (Thats my terms and condition) ., Now what will be the calculation on my bill / invoice. They are asking for Tax Invoice. For Sales of goods: 1) As I am not a GST registerd business owner, then what will be the billing calculation for the goods Actual value of 5000.00 ? Example: Actual value=5000.00 GST 18% = 900.00 ------------------------------- My buying Price = 5900.00 ( as I am not registerd GST holder, I think I cant claim) My Sale Price (20% margin)=7080.00/- After 7080/- what will be my goods invoice? For both the case, if any body send me two separate xls sheet, that will be very helpfull for me. Thyanks in advance. Mostafa Emotions Technology