My paycheck is being garnished $305.00 per mt, I.R.S $495MT child support.$250.00pmt.?

I am overwhelmed I only make $2400.00 per month. I can not even afford to buy my child cloths for school. I have tried to deal with the I.R.S. and Ca shesta and San Bernardino chils support officals but they will not lower the payments to an affordable rate. These garnishments create a great hardship for my family not to mention marital problems.I need some kind of help. I can,t afford an atty as there taking all my extra money. I live in wa what can I do?