Student self-enrolling in the Turnitin anti-plagiarism service is chosen by staff at Lancaster University for some courses. The idea is that students can upload copies of their work to the correct assignment in a course area themselves, and can then use the software themselves to check that there's nothing wrong with their work. Doing this is really quite easy - you have to enroll, as shown, step by step in this section, then upload work, as shown in a following section. Then you'll be able to see your report, and the last section of these instructions gives one or two tips on why the percentage of your essay that Turnitin found matched with the internet might be too high and what you can do about that.
Things to have before starting enrollment:
Before starting, you will need to have the TurnitinUK class ID and the TurnitinUK class enrollment password. Both should have been given to you by your tutor. You will also need an email address. This is used as your login to the Turnitin service, and you may be contacted on it by your tutor, so it needs to be a valid one that you look at quite often.
The step-by-step guide to enrolling in the service:
Go to http://www.submit.ac.uk

Click on the "sign up" link and then click on “Enrol as a student”:

… and then click the “click here” link.

You are then asked whether you'd like to enrol as a student, instructor or teaching assistant. Choose "student".

You'll then need the TurnitinUK class ID and the TurnitinUK class enrollment password supplied to you by your tutor. These enable you to enrol in the right class:

After this, you'll be asked for your name and your email address. If there's someone else in your class with the same name, you might want to add an extra bit to one of these fields so that your tutor knows that this one is you.
The email address will become your login's username on the Turnitin service. You should probably use the email address that your tutor uses to contact you.
Next, you'll be asked to make up a password for your account. Suggest writing this down somewhere safe.
After the password, Turnitin asks you for a secret question and answer. This saves time getting another password if you forget the one that you put in - if you can remember your secret question, and the answer to it, you'll be emailed your password.
The last thing that you have to do is agree to Turnitin's licencing agreement, and then you can click the button to create your profile and enroll you. The screen at the bottom of this page appears, telling you what to do next - login to Turnitin, and then submit work.
To submit work, extra instructions are available in section 4: Submitting work to the anti-plagiarism software.