I had the same symptoms with Xeloda (oral 5FU).
For mouth sores I was given a suspension of lidocaine and an antifungal agent to be used as a mouthwash.
For hand foot syndrome, unfortunately there is not much that can be done except use a lotion like Aveno. I had severe hand foot syndrome during one of my chemo cycles. The dose was dropped by 25% for subsequent cycles. You can look on the internet for other precautions for hand foot sysndrome (e.g. avoid hot water).
Best wishes.
Tom