Alternatively, you can:
- go to the the 'User Control Panel' function (under your username at the top right hand of the page),
- then the 'Board Preferences' tab at the top,
- then 'Edit Display Options' tab on the left
- and finally then go to 'Display post order direction' at the bottom on the right.
If you set this to 'Descending Order' the newest posts will be displayed at the top of the first page in each thread.
Here endeth the egg-sucking lesson...