Go to Google Scholar page and click on 'My profile' at the top left corner of the window.
On your Google Scholar Citations profile, click on the '+' icon above your list of articles. There are three ways to add articles from here. 'Add article groups' and 'Add articles'offer suggestions based on your profile and you can check the articles you want to add to your profile. 'Add article manually' allows you to input the citation information for articles that don't appear in the automatic options.
To add articles manually, you need to add the citation information for each document. Select the type of publication from the options given and fill out the form with the needed information.
In addition to adding publications to your profile, there are also options for you to merge, delete and export records on your Google Scholar profile.