A colleague of mine, Clint Edmondson, has collected a board set of useful coding standards for C# that can be found here.
I am going to reproduce (e.g. copy) the set related to capitalization and naming in C# below. I do encourage you to see the complete set of coding guidelines from Clint here though as he has gone a great job in documenting these.
Follow the standard Naming Guidelines set by the .NET framework team by using only three capitalization styles: Pascal, Camel, and Upper casing.
Classes & Structs
Constants & Enums
Variables, and Attributes
Camel (private, protected, local)
Pascal (public, private, protected)
o In Pascal casing, the first letter of an identifier is capitalized as well as the first letter of each concatenated word. This style is used for all public identifiers within a class library, including namespaces, classes and structures, properties, and methods.
o In Camel casing, the first letter of an identifier is lowercase but the first letter of each concatenated word is capitalized. This style is used for private and protected identifiers within the class library, parameters passed to methods, and local variables within a method.
o Upper casing is used only for abbreviated identifiers and acronyms of four letters or less.
Follow the standard set by the .NET framework team when it comes to naming. The Programming section of this document provides naming templates for each construct within the C# language. These templates can be used in conjunction with the tables provided in Appendix A. Naming Parts & Pairs to yield meaningful names in most scenarios.