To get started using Safari's content, go to: https://www.safaribooksonline.com/library/view/temporary-access/.
Enter your ohio.edu email and click Let's Go. This will grant you access to the Safari content for three days.
The first time you use the temporary access, Safari will send you an email with information and a link to create an account. Once you create an account, you should have access to all of the Safari content just by using this account log in. The password does not need to be the same one you use for you ohio.edu email (and probably shouldn't), but you do need to use your ohio.edu email.
If you are linked directly to Safari content, you will likely see a preview of the content and an option to start a free trial. Example below. In this case, you'll need to go to the log in page.
If you do not have an account, follow the instructions above to make one, or go to https://www.safaribooksonline.com/library/view/temporary-access/ and enter your ohio.edu email to register for your device for access for three days. Then return to the Safari content from the original link.
You should now be at the log in page. This will use your ohio.edu email and the password you created when you set up your account.