Hi @jo9,
Thank you for your question about how to change a washer in your square shower taps.
Also, welcome to the Bunnings Workshop community, it is fantastic to have you join us.
Unfortunately, it's very difficult to offer specific advice on how to replace the washers without seeing the specific taps you are referring to.
If possible, could you upload some images of the tap? This will help our members to offer advice relating to your specific taps.
If you require assistance with this, please ask, I am more than happy to help.
In the meantime, you might like to check out How to replace a tap washer for a general guide.
Let me know how you go.
Jacob
