If you have a Google account (that you can use for all Google products), you can use the My Library feature of Google Scholar. Separately, you can change some Google Scholar settings. If you are signed in to for example, Gmail or YouTube, when you open Google Scholar, you will be signed in automatically. You don't need a Google account to use Google Scholar, but you do need to sign in if you want to use My Library. The sign in link is on the top right-hand side of the page.
The My Library feature in Google Scholar lets you save articles directly from the search results page so you can access them again at any time. You can organise these articles into folders using labels that you create and edit the details that appear in your reference lists. Using the My Library feature is a good way of keeping track of articles that you're interested in and organising them for use.
Below a search result, click 
to save the result to your library. When you do so, a notification will appear on the bottom left of the page. 
You can click 'your library' to see your saved articles.
The star's outline is now filled in -
- to show that the article's been saved to your library.
You can access your library by clicking the link in the notification that appears when you save an item or you can access your library via the "hamburger" menu 
Click on this to open a list of options
There's a small menu bar with icons above your library items. We'll explain of each of the icons are for
1 Select all items. You need to select an item to perform an action on it. Tick this box to select all items
2 Edit the details of an item - change the title, or the authors etc
3 Delete items
4 Export the citation to a file - to import into reference management software such as Zotero
5 Create labels to organise your library items into folders
6. Select an individual item
Perhaps of better use than My Library is the ability to set up alerts to receive an email when articles that match your searches are published. To set up an alert
Run your search
Click on the Create alert link
Check your details (search keywords, email address, number of results to display - 10 or 20) and click Create Alert
You will receive an email to confirm that you want to set the alert
Note: you don't need to be signed in to Google to create an alert - you can enter an email address in the Create Alert box
If you have published articles, then you can create a profile, which lets you showcase your publications. You can check to see if anyone is citing your articles and get some statistics about citations. You can also make your profile public; this is the profile page for physicist and author Richard Feynman and here are Google's pages on setting up a profile.
This really isn't the space to get into metrics, but basically one way, an important way, of measuring the impact of articles, is to look at the number of times they get cited by other authors. The Metrics section provides information about the most cited articles and most cited journals.
You can change some settings in Google Scholar including:
