IIRC the LCD component data sheet explains which connections you need to make for your LCD. Configure the component to use the 4bit mode.
Also, make sure that the GPIO pins used for the LCD are not used by other components / peripherals (check with the -059 schematic).
There are not special pins reserved for the LCD, but the pins must be 7 consecutive pins of the same PSoC port (again, read the component data sheet).
You can try to connect your LCD data lines to bank P0 ... P0 but there are external capacitors connected to ,, that you would have to remove from the board. You can connect the LCD to bank P12 but this might limit your ability to communicate via SPI or I2C. I found that PSoC Creator likes to use P12 for s_clk. This might not be a problem if you lock the s_clk to another pin but I haven't tried it. Then connect appropriate power lines to your LCD.
Thank you guys ! I'm happy to say to you that our project works well ! :)