How to build and solder?
The pictures are not of the most simplest transmitter but how-to is the same.
Make 5 x 5 mm squares.
This size is not random nor appearance of good shape but is designed by
the theory of "micro strip line" circuit
Drop a glue gel. The glue must be strong enough for fasting the squares on the board.
Paste a square on the copper-plated board one by one.
Solder on the surface of the square.
Fill the surface by solder.
Start to solder each components one by one.
Solder on the ground.
Every lead of the component must be soldered at the shortest distance.