Ok so if it's definitely going to be a big night then ensure you check your BG levels at least every hour, try and drink some water in between, make sure the people you are with know how to treat a hypo and what the signs of a hypo are so have a good buddy on your side who can keep an eye on you, aim to keep your levels above 6. Try to avoid sugary drinks and cocktails, they will send you high, slimline tonic and gin/vodka is best.
Also hypos can hit after drinking so finishing the evening with a snack/bag of chips etc is a good idea, for the sake of one night being high is better than being low.
Also perhaps just have a think about if it's worth drinking alcohol, particularly in moderation, the stress of checking levels and fear of going low is enough to put most off as it's not worth it, also good to be in control if you do need to sort yourself out, alot harder to manage when under the influence, whatever your decision hope you have a great night out.