Hi Tom
I use a piece of string about 4mm diameter. Hook one end of the spring on the exhaust and loop the string through the other
end of the spring.
You can have the length as long or short as you need depending where your springs are, some can be a bit of a pain to reach. I find this the easiest way for me. I used to use a purpose made wire hook on a T-handle, but the string is far better.
Cheers Mark