How to organize patch files? Many files or a single one?

What is the best way to organize the patch files? Imagine you have a patch file for an open source application and you modify it and want to keep the modifications in a patch.

What is the best solution: add the new modifications to the other patch i开发者_StackOverflown order to have a single big patch file or create the second patch file and have a bunch of them one for each modification.

If you choose the second one, what about patchs that modify the same files and lines and therefore can cause conflicts while patching? Do i have to stablish an order?

One patch per issue posted to the projects issue tracker. Otherwise, keep your changes in Git or whatever and use a branch for major projects. Often I have a branch for each module, then a branch for each patch that I'm working on.