To install Zotero on your personal computer or laptop and create your online account for syncing:
1) Visit https://www.zotero.org/download/ and follow prompts for your browser and operating system. Download and install Zotero 5.0 for your operating system (Mac or Windows or Linux) on your laptop. Also install the Zotero Connector for your web browser (Chrome, Firefox, or Safari).
2) Click Register in the top right of the zotero.org page to create a free online Zotero account for syncing online."
3) Installing Zotero should also install a Word add-in that lets you integrate Zotero with MS Word. When you open Word, you should see a Zotero tab in the ribbon, or a Zotero toolbar on older versions of Word.
If you do not see this, or if you ever need to reinstall the Word add-in, go to Zotero, open Preferences, go to the Cite tab, click on Word Processors, and click on Install (or Reinstall) Microsoft Word Add-in.
4) To set up syncing between your local Zotero library and you online Zotero account, open your local Zotero Preferences, go to the Sync tab, and enter your account information. You can also choose whether to sync automatically, and whether or not you wish to sync full text PDFs.
5) Zotero comes with a handful of popular citation styles installed. To add additional styles, go to Preferences, pick the Cite tab, and click Styles. Then click on Get additional styles... and find the style you need by searching in the large list of styles presented, and then click it to add the style you want.