Should a Non-Catholic Sign Himself?
Would it be appropriate for me to use the sign of the cross when I pray if I am not Catholic yet?
Certainly you may and should make the sign of the cross. It is not reserved for Catholics, and it is a powerful prayer for enlightenment and protection. If you make it while saying, "In the name of the Father and of the Son and of the Holy Spirit, amen," then you are combining an act of faith in Christ's Cross and Passion with the profession of faith in the Holy Trinity, and this will be very good for your soul. But become a Catholic as soon as you can. I will pray for you.