How To Modify/edit The Packslip Format

I want my pack slip format like snapdeal's packslip, which have barcode of tracking no ABW and return address, type of payment e.i.prepaid or COD.

[font=arial, sans-serif][size=3]Amends required:[/size][/font]

[font=arial, sans-serif][size=3]1. In the backend, we need to select if the order is either - Prepaid or COD[/size][/font]

[font=arial, sans-serif][size=3]This will show on the packslip.[/size][/font]

[font=arial, sans-serif][size=3]2. Every order has a unique AWB number as shown on snap deal packslip.[/size][/font]

[font=arial, sans-serif][size=3]I can enter this in the back end somewhere? So it appears on packslip[/size][/font]

[font=arial, sans-serif][size=3]in number format and also in barcode format - as shown on snap deal[/size][/font]

[font=arial, sans-serif][size=3]packslip.[/size][/font]

[font=arial, sans-serif][size=3]3. We need seller details on packslip too so if the order is returned[/size][/font]

[font=arial, sans-serif][size=3]it comes back to us:[/size][/font]

[font=arial, sans-serif][size=3]Seller details:[/size][/font]

[font=“arial, sans-serif”][size=3]Example Saller,[/size][/font]

[font=arial, sans-serif][size=3]256, Lodhi Road,[/size][/font]

[font=arial, sans-serif][size=3]Delhi[/size][/font]