mail

when i am sending emails the size of the font is about 5 or 6 how do I increase the size

1. Highlight text.
2. Press command-plus (the command key and the "+" key)
3. Repeat until the text is the size you want it.

Or, alternatively:

1. Highlight text
2. Click on the Format menu in the menubar, select "Show Fonts"
3. Adjust size there.

(this can also be accomplished by pressing command-t)

You can also go to Mail, Preferences and then Fonts & Colors and seer the fonts you want to use, including style and size.