Use this command to modify your working copy according to the change information provided in a patch file. You can create a patch file from within the Change Report window.
Select the patch file and click Next to read the file.
After reading the patch file, all files to patch will be shown. If you only want to patch some files, unselect the files you don't want to patch. In the table column Switch to Revision you should see the revision to which the patch will be applied. Click Next to continue.
On this page you can define a change set which will be assigned the patched files. Using this feature is especially useful when you already have modified files in the working copy. Click Finish to start patching. The files will be updated to the given revision and then the patch will be applied.