Summary: A Detailed Tutorial On How To Make A Binary adder/ Multiplier
To Learn How to design An ALU from Transistors Is A Rare Skill, However It Can Be Learnt:
First: Instead of seeing the transistors as individual components, Bunch Them into LOGIC GATES like AND, NOT, NOR, XOR, and OR (these will be needed to make an ALU)
Next: Use a basic design that you can UNDERSTAND And REALISTICALLY COMPLETE based on your knowledge of components and Soldering (See my blog on how to Solder) I recommend you Use THIS full adder circuit using 9 NOR gates Totaling ONLY 9 transistors per full adder!!!
Finally, Once Created, Make Sure to Double Check ALL connections, ALL Logic gate placements And then get it!
Check all modules induvidually