You do not need to think in terms of DTE and DCE.
Simply work this way: the TxD signal on the computer must reach the RxD pin on the MCU, through the RS-232 transceiver. And the RxD pin on the computer must be connected to the TxD pin on the MCU, again through the transmitter.
So make sure you connect the MAX232 properly, that is, its "receiver" should have the input connected to the TxD output on the computer and its output to the RxD pin on the MCU. The "transmitter" in the MAX232 should have its input connected to the TxD pin on the MCU and its output to the RxD signal on the PC.
The question of the cable then comes about if you use a 9-pin female or male connector on your MCU board. If you use a female connector on your board, then wire it as a DCE. If you use a male connector then wire it as a DTE and make sure the cable is a crossover one.