-choose the Rectangular Marquee tool then select a square in the bottom of the design :
Rectangular Marquee tool 
select Gradient tool Then press "D" Button ....... set a gradient from up to down ..... then Cancel the selection.
- Select Smudge Tool .... and with the help of smooth brush
start to merge white and black colors as in the example
to get better action use a small size brush in the ends
Then paint the Design in red color .... By choosing Image--->Adjust---->Hue/Saturation
- do what you see is suitable for your design .... and don't forget to select Colorize
- make a new layer ....... then colorize this layer with yellow color ...... then change the layer type to Multiply
the finish view will be near to this design
Thank You
