Hiring a speciality office cleaner is often the best way to keep an office clean, as they have the correct tools and skills for the task at hand.
If you want to try to do the work on your own, perhaps if your budget cannot quite stretch to having professional companies coming in, then there are a few things you will need to know before you begin.
The first thing you will need to do is create a cleaning schedule, to help you maintain the office cleaning so nothing is missed each day. This can be a simple timetable where you plan out when each part of the office will be cleaned. The best thing to do is map out the main areas which need cleaning well daily (such as reception areas, carpets and toilets) and the rest can be slotted in according to when there is time.
Make sure you purchase sufficient cleaning products which will last a long time. It is possible to buy large, bulk amounts from specialty cleaning suppliers.