Steve,
A rose is made just from red grapes.
When you press red grapes the juice will be white.
When soaking the juice in the pulp the wine will become red as all colour is in the skin and not in the juice.
However, when soaking the juice just for a few hours you will get a rose, and not a dark wine.
That is the proper procedure for making a rose.
Now it is off course possible to blend a red with a white to make a rose that way.
Trial and error is the way to go. Mix in certain proportions and keep tasting til you find which mix you like.
Luc