prefer the standard room to the business room
Just in this case of hotel it’s the smaller but cosier room, and it’s got a bathtub – at the lower rate (saves your customer money)

take tea candles (and matches, if you don’t smoke) with you ( preferably those which do not trigger the fire alarm! But my experience with fire alarms is that candle lights don’t do harm, while frying German Leberkäs does ) so that the evening in the bathtub gets romantic even without inviting your colleagues of the different sex.

Get tipsy in the evening (red wine if you want to sleep more, or french coffee, for less than four hours of sleep)
Makes you, your colleagues and clients more conversational, and if you are even in a foreign country, you’ll unrestraintly speak Dutch without ever having learned it. Plus, the solitary languishing in the bathtub feels like a candlelight dinner of two.

have a bottle of water
Drinking a liter of water after having gotten tipsy makes your presentation at the client the next morning at 8 a.m. bearable

S/M yogis: Take your yantra mat with you
Some people can only relax after a long working day when suffering pain.

get you a new hair coloring prior to the business trip
You should really balance reasons for or against a new hair color before you start your trip to the customer and using innocent hotel towels. Will you meet the dress code agreed with your client? Does the hair color fit to your outfit? Or to the corporate identity? Timing might also have a certain relevance. In my specific case, I knew before that it will be looking good, it was even necessary, because my one and a half week old ‘poppy red’ was already fading, my clients logo type has the same color, Belgium seems in general being a very open-minded country, plus we arrived in the week of carnival and it turned out that the IT-manager recently dressed up as a woman with a wig in the same poppy red. The hotel i’ve been staying however will probably ask for my planned hair color prior to confirming my next reservation. ( p.s. i looked different to this freak)