Your Moodle site has a built-in editor. There are 2 common types of editors within Moodle, but they're pretty similar. Getting familiar with your editor is a good way to get development started.
Here's a summary of some common buttons found in the editors.
|Undo and redo actions|
|Find, or find-and-replace text|
|Switch fullscreen mode on or off|
|Align text on left, at centre or on right|
|Format painter, format remover, paste as plain text, paste from Microsoft Word|
|Select a colour for text or text-highlighting|
|Text direction (left to right, or right to left)|
|Set as bullet list, numbered list; decrease indent, increase indent|
|Insert or edit a link, remove a link, prevent automatic linking|
Insert media: image, emoticon, embedded media (sound, video or applet), manage embedded files, equation, media gallery, non-breaking-space character, custom character.
When embedding audio, use MP3 files for the best performance.
|Insert a table|
|Toggle HTML source mode|