To start a new message to send, click the Compose button in the upper left corner of the TouchMail window:

In the compose window that appears are options to add recipients, change the account to send the message from, attach files, and more:

In the message reading window you can see information about the email, delete the message, move the message to a folder, reply, reply all, print, archive, and more using the buttons and "..." menu on the right side of the window: