Are you using my zips for system rw? If so then since twrp is on the boot partition and the boot.IMG is on the recovery partition, you need to hold power + volume up to boot into android and turning the phone on with just the power button will boot you into twrp recovery.
If twrp is getting stuck at the splash screen and not booting all the way then that means that the image is corrupted. This would be caused by a bad download.
Either way, whether you used the switcher zip or not, please let us know exactly what you were doing before this happened and try to give as much detail as possible. Your answers to our questions help is figure out what needs to be done to remedy your situation.