sure to get the same kernel version that the patch applies to.
Assuming that the kernel you just downloaded is linux-x.y.z.tar.bz2, unpack it as follows:
$ bunzip2 linux-x.y.z.tar.bz2
$ tar xvf linux-x.y.z.tar
You should now have a kernel source tree in a directory named linux-x.y.z.
Assuming that the name of your patch file is /tmp/my-patch-x.y.z.gz, apply the patch as follows:
$ cd linux-x.y.z
$ zcat /tmp/my-patch-x.y.z.gz | patch -p1
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