The first step in break-in is to realize that each of our feeder answers has exactly nine letters and exactly three O's. The game numbers (13, 15, 19) are an extra clue as to which game to match each feeder to - via A1Z26 we get 13 = M, 15 = O, 19 = S, which gives us the first letter of the corresponding feeder answer for each game. Then, we overlay each answer on its respective tic-tac-toe grid and place X's as indicated by the clues:
To extract, we take the letters that the X's are placed over, and order by the numbers given in brackets. The image gives the order in which to count. For example, for MONOAUDIO, the [3, 4, 7] applies to A, U, I in that order, so A is in position 3 in the final answer, U in 4, I in 7. This gives us the final answer BEAU TYING, i.e., tying your beau in tic-tac-toe is the skill you must master.