when you are viewing a profile, click "send a message" button under the profile picture of the user. or, when you are viewing your inbox, click the "compose a new message" link and start typing your friend’s name that you want to send the message to.
when you are reading a message, you will see a platform where you can type. write your message here and then click the “send” button to reply to the message.
if you have not done any privacy adjustments, any eupee member can message you. however, you can manage who can send you messages! to do that, go to your "privacy settings" first. when you are in "privacy settings" you will see some options about your profile. from the boxes next to "messages, actions and friend requests", you can select any option of your choice. for example; if you do not want to receive any messages from anyone, select "no one". now, not any eupee members will be able to send you a message. or, if you want to get messages only from your friends, select "my friends". now you will receive any messages from no one, except your friends.
when you are in your inbox, you will see the "delete" link next to every single message. click that delete link next to the message, which you want to delete.