Use this scam report format to accuse someone with all valid proofs that will proves that he scammed you.
[b][color=black]What happened:: [/color][/b]
[b][color=black]Scammers Profile Link: [/color][/b]
[b][color=black]Reference Link: [/color][/b]
[b][color=black]Amount Scammed: [/color][/b]
[b][color=black]Payment Method: [/color][/b]
[b][color=black]Proof of Payment: [/color][/b]
[b][color=black]PM/Chat Logs: [/color][/b]
[b][color=black]Additional Notes: [/color][/b]
And don't forget to add the screenshots of your conversation with this user, It's really recommended to used an escrow, it's a big help to avoid of being scammed from some newbie accounts here.