First of all, you need to download the plug-ins from the plug-in developer’s website. Once you have the plug-in file, you can upload it to your WordPress plug-ins directory, using FTP.
On the other hand, if you do not want to follow the process of downloading the plug-ins and then uploading them one by one, then you can also do it directly from your dashboard. Just point your cursor to the Plug-ins tab available at the left bar, and you will see a sub-menu appearing on the screen.
Click “Add New”, to add a new plug-in to your dashboard. Here you can search for different plug-ins that can make your life easier, while working on WordPress.
Google (XML) Sitemaps Generator is a great plug-in which will helps you in telling Google about any changes made to the XML sitemap of your website. When you register your website with Webmaster Tools of different search engines, such as Google, Bing, Yahoo, etc, they ask you to enter the sitemap of your website.
Here, you will give the link of the page which the Google (XML) Sitemaps Generator created. Each time you will create a new post, the XML sitemap will automatically get generated and the plug-in will also ping all the search engines about the changes made.
WordPress SEO is an amazing plug-in, which allows you to enter the Meta description, Meta tags, and Meta title of the post you create. It also helps in making optimising your content for the search engines. Currently, it is one the best SEO tools available online.
If you want to increase the website’s loading speed, then you should consider installing W3 Total Cache, as it dramatically increases the user experience of your website.
If you want the visitors to comment on the posts you published, then you can install Disqus Comment System, as it allows the user an easy way to post their comments, after following an easy registration process.