Please can someone explain how to send money using BACS with Halifax

Hi,
I am trying to transfer some money between accounts (Halifax and Lloyds). I have been told by Halifax that I can send payments of £1000 each day using BACS. Please can you someone give me detailed instuctions on how to do this because I think I know how but I want to be sure

Thanks in advance

P.S Just checking, if you think Halifax will charge me, please let me know.