Simply download EasyPHP from
http://www.easyphp.org/, after it installs, just run it, call up the main interface from the button thats shows in the tray area, turn off MySQL, iconize, and point your browser to your local IP, you should get the EasyPHP help page, this is the first stage done.
Downaload the DokuWiki archive, unzip it to the /www folder which will be under the path you installed EasyPHP, then just call up the local ip again, in that menu you will see a folder called "dokuwiki" or whatever folder you unzipped the dokuwiki to, click it. You are now running the wiki. That easy.
I run a local one on all my systems now, mostly for use as a "notebook", I use to have a folder full ot txt files, but this is much better, its linkabkle and searchable. Awesome.