You need to design a base for the acrylic to stand in.
Using inkscape or your chosen design software draw a rectangle 120mm x 40mm
Copy the rectangle and paste it alongside the first rectangle.
Draw another rectangle 100mm x 3.2mm and position it in the centre of the second rectangle so that it is evenly spaced.
Copy the 2nd rectangle, including the narrow rectangle inside, and paste it alongside the others.
Change the sizing of the narrow inner rectangle so that it measures 10mm x 111mm. keep the vertical alignment central but move the horrizontal position so that it leaves approx 1cm at one end and overlaps the other end by 1mm
Save as a .dxf file, import into laser cut software and send to cut from a 3mm sheet of plywood or acrylic.