Since the subject mentions wordpress. The 1st thing you will need to find out is if your hosting supports both PHP and mysql. After that it depends on how your host and your configuration is setup. If you are on a dedicated solution the web platform installer or a manual install will work if the sever has enough extra resources. On non-dedicated you will need to figure out hot setup a mysql database through your control panel/host. Once that is done it is mostly do a manual install by copying wordpress files over to a new folder. And then follow the rest of the install steps in the wordpress documentation.
If your hosting does not support either you may want to consider alternatives. Make sure you hosting supports hosting more than one database for your plan. If it does then consider BlogEngine.Net since you should already have .net running.