Thanks for using Aspose APIs.
Not all properties of Style objects are required by you. A complete Style object with default properties can be created using Workbook.CreateStyle(), so there is no need to save the default properties. You only need to save those properties which are needed by you.
It means, you should save only the properties of your interest.
However, if you want to serialize the entire Style object, then we have researched a bit and found, there is XmlSerializer class which serializes the .NET object into XML. There might be other serializing objects or classes in .NET that serialize the .NET objects.
Please research on internet how to serialize any .NET object.