The switches utilize MDIX and do not require a crossover cable for switch to switch connectivity. Not taking MDIX into consideration, a crossover cable would be used for switch to switch, while straight-through would be used for end devices.
The 2724 and 2824 switches are very similar. You should be able to configure it using the same steps as the 2824.
Just a quick follow-up -- after making the changes to specific switch port CoS as needed, the sound quality of VOIP calls is much better. Thank you!