This circuit is a standard diode Transmit/Receive switch used in many radios. In your case the quarter wavelength line is most easily implemented in microstrip. Microstrip line is a pcb trace on the surface of your board, backed by a ground plane under it. The width of the trace, and the distance to the ground plane are both critical dimensions, so we need to know what the dimension is, in your pcb, from the underside of the top copper layer to the closest surface of the ground plane layer. From this, we calculate the width of the trace. Once you know that, then the remaining critical dimension is the length of this trace, which we estimate using the velocity factor of your particular pcb. For this, we need to know what dielectric is used in your pcb.
Knowing the width and length, it is just a matter of laying this out on your board. When laying out microstrip, you have to keep any ground plane that is on the same layer as the microstrip trace away from that trace by at least the width of the trace. You may turn corners with the trace, but it is better to keep it straight if this is convenient.
If you are not laying out a pcb, then the obvious alternate is to use a piece of small coaxial cable, and cut a coax jumper that is one quarter wavelength long. Calculate length using wavelength=speed of light divided by frequency, then multiply by 0.25 to get one quarter, then multiply by the velocity factor of the cable you use.