Download dash launch 2.26, run it in sex menu and patch it onto the console, thee is also a sample_launch.ini in the dash launch package you need to put on your internal hdd on the root of the drive ( not in a fold) in the ini, you need to change the line in there where it points to the FSD xex file, eg: hdd:/FSD/default.xex
You need to rename the sample_launch.ini to just launch.ini too
I'd suggest putting freestyle dash in a folder called FSD on the root of the hdd to keep it simple.
1: download dash launch
2: put the installer folder on your Xbox hdd (assume u know how)
3: rename the launch.ini and change the line to point to where your dash launches default.xex file is
4: go into xex menu and navigate to the "installer" folder you just put on and launch it.
5: follow the prompts, apply what settings you want. ( if your unsure google what some do, but most are straightforward ) the console wil want to shutdown after it installs
6; fire up the console again, provided you have put your ini on the root of the hdd and have it pointing to the correct dir of your FSD default.xex it should launch into FSD.
To boot to nxe the default is hold down RB while the console is booting
Hope this helps