C# Relative Folder Directory Structure via Savepath filename

My goal is to "Build a Relative Folder Directory Structure base Save path filename". Can someone give me directory to approach this below and and how would you write the logic. I have an ideal. I just want to get others concepts to make sure I am taking a robust approach. Essential and A user is created project on local disk. The user browse to project destination of choice on local pc. Where ever the project xml filename is save create the relative from the xml file. The xml contains all project configuration data.

Example:

INPUT PARAMS BELOW:

string filename = "redColorName"; //user enter filename

string savefilepath = "c:\\temp\"; //user browsed to path

REL FOLDER OUTPUT:

The folder name should be the filename and I just append and the data to the filename like below.. I added unputFolder and outputFolder.

..\redColorName_inputFolder\

..\redColorName_outputFolder\

..\redColorName.xml