Excise on sale of goods meant for advertisement purpose

Dear Experts,

We are manufacturers of excisable goods (garments).  We seek certain clarifications on account of the following scenario.

Let us consider, a customer orders garments with his logo/label/print on the garment for advertising purpose on account of sales promotion of his own product, say for example cement.

1. whether the sale of garment as per specifications of the customer comes under sale of branded readymade garment an excisable goods

2. If yes, what should be valuation method of assessable value.

Regards,

Govindarajan R