Dont worry. Call the property - not the general Hilton reservation line - and explain that you will not be able to make it to the hotel on day 1 but you will arrive for check-in on day 2. This is called "late check-in" and is quite normal - it happens very day - front desks are used to deal with this.

If this is prepaid/non-refundable stay, the agent will note "late check-in" in your reservation and you should be able to check-in at on day 2. If it is a non-prepaid/flexible reservation to be paid at check-out the agent will most likely remove the first night without a fuss (and obviously without recalculating the rates for the remaining nights). I have done this several times without problems (i.e. without recalculation of the rate) but you need to speak to the hotel rather than the general Hilton reservation/phone agents (the latter can't do it).

BUT as the previous poster explained: You have to call the property and explain that you will arrive for check-in on day 2.