First, typically it's not a good idea to create a backup on remote computer. If this is just a single case, then fine. But if you're going to do this repeatedly what's going to happen for example in case of a network failure, you don't have a backup at all...
But to the answer. This can be done in numerous ways. The easiest way is direct the backup to remote computer is to use UNC paths. You can use them in the backup command or you can predefine a dump device. Te get more info, have a look at
sp_addumpdevice[
^] and especially example B.