Hi there,
I can definitely advise you to establish a routine as early as possible. It will help you to know when things are due and keep your motivation up. Most people find studying around 8-10 hours per week is satisfactory for doing well. Also, don't be too hard on yourself if you don't originally get amazing marks - it's a big learning curve and it takes time to adjust to the OU way of doing things. Get to grips with referencing early on!
All the best on your study journey. :0)