Slide your finger left on the display.
Tap Messaging.

Tap +.

Key in the first letters of the required contact.
Matching contacts are displayed.
Tap the required contact.

Tap the text input field.
Write the text for your MMS.

Tap the attachment icon.
Go to the required folder.

Tap the required picture.

Tap the send icon when you've finished your MMS.

Tap the Home key to return to standby mode.