Parking in Oxford

What counts are "most convenient" would be a value judgement, but I can present some options.

Oxford's traffic and parking is in general pretty bad. July should be a bit quieter, because of summer holidays, but a weekday does mean that workers will be using most available parking space.

Your lowest-stress option is probably to use a park-and-ride facility. With these, you park your car in a large, easy-to-access car park outside of the city, and then get a bus in to the town centre. The prices vary depending on which car park you use - Pear Tree and Thornbridge both mention being accessible from the M40, which fits with your itinerary.

Somewhat unusually, payment for parking and bus is apparently separate in Oxford. You can find more about the bus services (and fares) on the OxfordBus site.

If you wish to park closer to the city centre, it seems that most parking is operated by Oxford council. If you are able to arrive and leave outside of peak commuter times, this might not be too bad an option. You can find out more about the council parks (and rules) on the Oxford parking site. One notable option is to reserve in advance a permit at the Oxpens site, guaranteeing you a space - although it is about 20 minutes walk from the University.

I don't know what the options are with regards to on-street parking, especially on the out-of-centre side of the University, but from what friends and family have told me of driving and parking in Oxford, I'd be surprised if there was much opportunity. Still, you could drive around having a look if you want. Just pay careful attention to signage regard availability and time limitations to avoid a substantial fine.