Before attempting either of these methods,
backup your NAND!
It's possible to get the DS profile exploit working on 7.2, but I wouldn't say it's very noob friendly.
Your 3DS's MSET (system settings) must be either 4.X or 6.X for the DS profile exploit to work. You can downgrade your MSET to 4.X or 6.X via cia installation (the cias can be found on "some iso site."). After downgrading your MSET, you can use
this version of rxTools to launch via MSET. You'll need to drag the rxTools.dat, the rxTools folder, and the cdnfirm.py generated firmware.bin to your SD card from the version of rxTools I linked you to. You'll also need slot0x25KeyX.bin on your SD card (you'll need to search for this online), otherwise the rxTools installation will fail (even on firmware 7.X and above). After that you can use the rxinstaller.nds included in the mset folder to install the MSET exploit via a DS flashcart (select 4.X DG if you downgraded your MSET to 4.X or 6.X if you downgraded your MSET to 6.X). After that you can launch rxTools via the DS profile exploit on 7.2.
A more noob friendly way to get the MSET running is to use the Gateway launcher to downgrade your firmware completely (note: this will make any saves on games that use the 6.X save encryption unusable). Grab the latest version of Gateway from the Gateway website and the downgrade pack for your region. Put the Launcher.dat and the downgrade pack from Gateway on your SD card. Run the Gateway launcher via web browser using one of the available exploit sites (
http://go.gateway-3ds.com,
http://dukesrg.no-ip.org/3ds/go2.html,
http://bobdoleowndu.github.io/3ds/go.html). On the Gateway launcher select the backup system NAND option and run that. After it finishes go all the way to the right on the Gateway launcher and select downgrade console. Run it. Once it finishes your console will be on 4.X firmware. From there you can use a DS flashcart with the rxinstaller.nds file to install the MSET exploit and launch rxTools via the DS profile exploit.