I´ve bought very inspirational book "Vibrant Acrylics" from Hashim Akib, so I was practicing with acrylics. The picture below is one of my first attempts. My intent was not to just blindly follow the instructions but also experiment with my own way...
The result is not super cool but I really like it, I was surprised how the underpainting makes a difference and impact of different brush strokes...the overall impressionist and sketchy look.. :)
Here comes the result - A4 hardboard 250g/m2, my own reference