DIY Doctor UK DIY Forums

Hi all hope this is in the right place. I have a metal front door which was painted (badly) by my OH . It is now all flaking off and in parts is down to the grey metal bitty underneath. After months of nagging still my OH has not touched it so have decided to tackle the bloomin thing myself, trouble is no idea how when where and why to start :? Could anyone help. Did look into replacing it but the builders who built this house used stupid non standard sizes (80x33inches) and I cannot find one anywhere.
Please please please help. I need to know how to go about it and what materials I need.
Ta muchos to anyone who helps!