Step 1: Write a problem statement for what you want to do
Step 2: Write an outline, if it is complex
Step 3: Write up a section in pseudo-code (English instructions)
Step 4: Write the section in the programing language of your choice
Step 5: Compile the program.
Step 6: Run your program and see if it makes the computer do what you wanted.
Step 7: If not, fix the program, and compile and go back to step 5. Otherwiae release / turn in your program.
FWIW, NathanOliver's post was spot on.
How far your game goes depends alot on the operating system, SDK and programming language. For instance, I ported an SDL tutorial based on Tic-tac-toe over to SFML and felt that further improvements can be made if SFML can simplify networking API (2 player mode) and/or Image class that supports copy-on-write memory management.