Be clear in the way that a photo will be understood by the recipient. If you’re sending a “miss you” shot from an overseas business trip to your girlfriend, make sure the passing group of convention models clad in short leather miniskirts won’t be misinterpreted. Retake!
Keep it brief: Just because the character limit of an MMS is longer than for SMS, this isn’t the medium to yammer on. Pick up the phone and call, or email.
Respect people’s privacy, which means, fellas, no self portraits in the men’s room with the lads lined up at the urinals behind you.
Get permission: Like above, also respect the privacy of those actively taking part in the photo or video and ask if it’s all right if you post it to the web. They may think it’s for personal use only.
Fill the shoebox: Memory on phones is limited and some recipients may not have the awesome plan you do to download MMS messages. Consider creating a moblog (mobile blogging) photo album online instead.
Reveal identities or details of your home, your car (blur the license, at least) or anything linking you to potentially malicious users online.
Shoot the sheriff: Rather, don’t film anything that could land you in front of one, including sending questionable material to underage recipients.
Get infected by opening an MMS from a recipient you don’t know. The spinoff is, most phone viruses spread via contact lists to every number stored there. Your friends won’t thank you!