No big deal - you need to remove the timing belt so make sure the timing marks are all lined up before you start, then lock the engine. The details are all in the manual so no point typing it all again here.
Then it's just a case of undoing the bolts and persuading the pump to come out of the housing - they can stick so have a plastic/copper/wood mallet handy, don't use a steel hammer. Make sure you get the old seal out with the pump - half the time they stick in place and people don't always notice, then wonder why the new pump won't fit right.
