Begin by opening up the red texture from the sample pack named Mercury Rising in Photoshop. Double click the Background layer to make it editable, then press CMD+T to Transform.
Scale up the texture while holding the ALT and Shift keys until the painted area fills the entire canvas. Hit CMD+I to Invert this layer to switch the red colouring to a bright blue. Alternatively, a Colour Overlay layer style could be used to specify an exact colour.
