Click and type wherever you want your text to go. Select the text then choose style elements from the toolbar.
Click where you want to insert links or images, then use the toolbar to insert such items. Hover over the tool bar icons for a second to see a tooltip about each one.
If you first click into a table or click to select an image, then you can right click for even more options. For example, you can now right click to insert table rows or columns.
You can copy and paste from many other applications, however it is likely to cause you some formating grief. Consider using the "paste text" or "paste from word" option just to the right of the insert menu.
There is now an integrated spell checker. You may need to install some software the first time you use this with Internet Explorer.