Two time signatures

Good evening Thank you to all those that help on these forums.
My question is how can I put two time signatures in at the begining of my music.
In doing this music enlarging for my mum I have seen a few pieces with two time signatures. I have not be able to do this.
Mum has written one out so I can type it up and this has also got 2 time signatures.
Does anyone know how to do it.
$ 3/4 6/8 eg. the 4 represents the cleff