To make your WordPress site more mobile-friendly, your easiest choices are to install either a plugin or a theme that is mobile-friendly. I don’t have any specific recommendations for you (and asking for recommendations is off-topic on this site), but there are lots of options to choose from.
Don’t run more than one “mobile” plugin or theme at a time, as they will likely interfere with each other.
It sounds like you’ve already chosen the WPTouch plugin. If this is installed properly, you should notice a difference when you visit your site on a mobile device.
To check that the plugin is installed and activated:
Click on Plugins, Then click on the “All” link at the top of the Plugins page. If you find “WPTouch” listed, then you’ve already got the plugin installed. If you see an “Activate” link for the plugin, then the plugin is deactivated. Click on the “Activate” link to activate it. If you see a “Deactivate” link for this plugin, then it is already activated.
If you visit your site on a mobile device and WPTouch is activated, you’ll see a slider button at the bottom of your page that the user can use to turn the mobile theme On or Off.