Before starting, you should check what can be observed in a specific night – which constellations are visible and which objects can be observed in them? This depends on the brightness of the objects and their size as well as on the performance of your binoculars.
In addition to a planisphere, which provides a quick overview of the sky and is ideal for orientation, there are a number of computer programs that will help you in planning – some also for smartphones.
Fortunately, there are also very good programs available as freeware, which have an object catalog sufficient for binoculars and are easy to use. For many programs, it is also possible to display the field of view – a very useful feature when looking through the binocular later. Therefore you don‘t have to rely on expensive professional programs. I highly recommend Stellarium and Cartes du Ciel.
Literature, including a good star atlas with annotations, will also aid in preparation, but there aren‘t too many books with maps and an object selection fitting for binoculars. There are, however, quite a lot of star atlases. It is only a matter of taste what you prefer or which one works best for you. To use the cards, it is helpful to prepare a field mask from wire that corresponds to the field of view of your binoculars. Alternatively, you can also draw or print a corresponding circle on transparency film.
Besides a star chart and binoculars, you should also fetch a red flashlight as a reading lamp. In contrast to a white flashlight it does not dazzle and saves your dark adaptation. For this you can use either a normal flashlight with red cellophane tape, or you buy a special flashlight with a red LED, as they are sometimes sold as a keychain. It should have adjustable brightness.
Do not underestimate the cold of the night – even in summer you should have a jacket at least within reach, drinks and something to eat are also good.