British Gas
All the normal advice for energy suppliers applies with British Gas. Submit a meter reading at least every month, if your Smart Meter not allready sending readings at least once a month allready, ideally daily to ensure covers price change days, else submit a reading just after prices change, every three months. Many Smart Meter are not communciating, so check. You can turn on more frequent reading being submitted in your BG Energy account. This is particualy important with BG as only six monthly billing for those on Direct Debit or often find even less frequently after change from old system to new, or if meters are not working well. It is still quarterly for those who pay on getting bill. Please ensure payments cover usage over a year if you don't want to get in debt. You can make one of payments and also change level of direct debit.
If you are not a domestic customer, such as industrial or commerical and that including landlord's supplies and often holiday lets, are not subject to Ofgem's domestic energy cap, but there is a scheme that does reduce costs durring price spikes but you need to make sure your tariff includes it. Often business use brokers to shop around for them for cheapest often three year fixes. Business deemed tariffs can be extreamly high and can be over a pound (£) per kiloWatt.hour (kW.h) from an example I have seen.