To install the Mendeley Plugin you need to first close Word and then on Mendeley Desktop go to Tools > Install <Your text processor> Plugin. If after installing the Mendeley Plugin you are unable to find the toolbar, please try the following:
1. On your text processor, go to View > Toolbars and select the Mendeley toolbar. You should then be able to see the buttons 'Insert Citation', 'Insert Bibliography', etc. In Word 2007 and 2010, you will find the Mendeley plugin in Word's References ribbon.
2. Try and insert a citation by clicking on 'Insert Citation' and a dialog window will appear. You can either type in the title of the reference you wish to insert, or click Go To Mendeley, and then selecting the relevant reference in your Mendeley Desktop.
3. If you click Go To Mendeley, the 'Send Citation to Word' button will appear on Mendeley Desktop. Click on it to send the citation to your Word document.
4. When you are ready to insert the Bibliography, simply click on the 'Insert Bibliography' button.