Good writing is all about muscle and motor control and hand-eye co-ordination.
Finger muscles are only gradually developing at this stage so it will help your child greatly if he/she is practised at colouring, drawing, painting, making jigsaws, cutting with a scissors, manipulating materials such as play-doh, blocks, lego, sand, jigsaws etc.
Your child will be learning to write lower case letters initially so it would be very helpful if you could encourage this at home.
Making letters on paper is not easy for the small child. He/she must learn to hold the pencil properly at an early stage and make regular shapes.
Stick up your child’s name on his/her bedroom door so that he/she can be familiar with its appearance. If he/she can be practised in writing it this is even better!
Don’t discourage left-handedness. If that is your child’s definite natural inclination, don’t attempt to change it.