You might try heading out and sailing into it for a few miles first before turning and running with it just to make sure that you are comfortable doing it.
Depending on the boat and the wave period, beating into seas of that size can be anything from hard driving to survival sailing where you are not making any progress. If the period is long and you have a boat well suited to the conditions, just power her up and you will get there. It will definitely put some extra stress on the people and gear so you need to be prepared. However, if the period of the waves is short, your boat can start "falling off" the waves which makes it extremely hard to cover any ground. This results in extreme pitching and the boat loosing most of its speed each time it comes down into the trough. The key in these conditions if you want to make any progress is to accept that you can't point very high and fall off a little to get your boatspeed up.
One of my favorite days on the water ever was a day with 10-12' waves with a very short period. We only went out for 2 hours or so and couldn't point above probably 60 degrees. When we went to tack, we discovered that the boat wouldn't do it, we could never get head to wind so we used the engine at WOT since we didn't want to gybe. There was also a race going on at the same time and some of the multihulls would launch off the top of a wave and move sideways 10-15' while in the air before hitting the next wave. While the wave height was not that great on these seas, the reason that it was so tough was the period.