Serialization of some extra information

with my physx scene I need to serialize (binary) some extra information, like 10 floats.
I looked into the custom class serialization snippet, but the example there is kinda complex.
If someone has a hint how to do this or has links to examples/ tutorials I really would appriciate it. Any approach is fine for me. Currently I write an extra file for this.

Thank you

Have you looked at these instructions for binary serialization, including information on the serialization of custom classes?