Yes, you can add acrylic paint to your glue to change the color of it. The proportion of paint to glue depends on the color you want to achieve: for a darker color, use more paint, adding a small amount at a time until the desired color is reached. Deep reds are difficult to achieve because the whiteness of the glue creates a pastel shade. However, most glues can be turned quite dark with just a small amount of paint. The color will remain the same when the glue dries.