How do I record mileage

I am a new sole trader and getting to grips with bookkeeping! I would like to know how I record business mileage when I use the .45 per mile option? What info do I need to enter etc. Hope you can help.

What i do is a journal either per month with mileage claims or at year end.I set up a new nominal code called mileage claims(7351) or you can use Misc Motoring costs (7304) and then you would do the journal.

Capital introduced (3000) mileage claims 50.00 credit column
mileage claims (7351) or (7304) 50.00 debit column

Hope that helps.