First, go to the website and log in to your personal account. Now, if you look at the navigation bar on top, you will see 'profile' on the right. Click on 'my account' and 'personal details' or 'my address'. Here you will see your personal details, which you can edit by clicking on the edit button.
Please make sure that this information is correct as this will be used to create your Solis ID. The way it is filled in is also how it will appear on your certificate of attendance.