You may have to get sorted with the bank on the first day so that money you take goes into your account and not the previous owners. It may be easier if you can for the first week to only take cash if you can just to keep it simple till you have your card machine sorted.
What you can do as an alternative is to use the card slips and one of those card slider machines (I am not sure of their proper name) and then put them through your new card machine when it arrives. I have also found that the banks tend to leave you to your own devices in regards to card machines assuming you know what you are doing. If you have never worked in retail or have never used a card machine they are relatively simple but if you want someone from the bank to come out they will send someone so ask. It is also worth trying it in advance with small amounts with your own card ie £1.00 to make sure you are familiar with the procedure it costs virtually nothing and it will make you more confident.