In a Cloud Computing environment we pay by usage. In such a scenario our usage costs are much higher. To optimize the Cloud Computing environment we have to keep a balance between our usage costs and usage.
If we are paying for computing instances we can choose options like Lambda in AWS, which is a much cheaper options for computing in cloud.
In case of Storage, if the data to be stored is not going to be accesses frequently we can go for Glacier option in AWS.
Similarly when we pay for bandwidth usage, it makes sense to implement a caching strategy so that we use less bandwidth for the content that is accessed very frequently.
It is a challenging task for an architect in cloud to match the options available in cloud with the budget that an organization has to run its applications.
Optimizations like server-less computing, load balancing, and storage selection can help in keeping the Cloud computing costs low with no degradation in User experience.