Now we need D-trigger. Simplest possible one is this:

Problems: it's transparent (when C is "1" then Q transparently outputs value from input D) and there are no ability to clear it besides D/C. So we will use more sophisticated one - this board has 2 of them (it's like functional analog of 7474 chip, but with buttons for set):

Pins description (from right to left):

1) GND - ground;
2) D1 - first data input;
3) ^C1 - first clock input (front active);
4) /R1 - first reset input;
5) Q1 - first straight output;
6) /Q1 - first inverted output;
7) D2 - second data input;
8) ^C2 - second clock input (front active);
9) /R2 - second reset input;
10) Q2 - second straight output;
11) /Q2 - second inverted output;
12) VCC - power +5V.