Managing your child's finances

Hi I would appreciate some advice please and would like to know how others' have managed this.

My son has severe learning difficulties as well as autism and cannot manage his own affairs. As his mum I am his appointee and have a separate bank account just for his money but it's still in my name. All the benefit agencies and the council have accepted this.

I am aware that I need to set up a new account for him so that his money will still be accessible after I die. Any suggestions on the best way to do this would be welcome.

Thanks