Fill a jar with sliced cucumbers. Add salt, sugar, pepper. Fill 2/3 of the jar with vinegar and the remainder with water. Store in fridge for 3 days prior to serving.
Notes
I use white wine vinegar but any vinegar will do. Remember that a balsamic will be sweet so omit sugar, and it will color the cukes. So will any non-white vinegar (like red wine vinegar).