I like Tetsujin's approach (see comments) re parental controls.
However, ifIf you must disable SIP within macOS Sierra, here are the steps involved:
- Startup (or restart) your Mac
- Immediately hold down the commandR keys to boot into recovery
- Click the Utilities menu and select Terminal
- Type
csrutil disable
and press return - Close the Terminal app
- Select Restart.... from the menu
NOTE
- I really do not recommend you keep SIP disabled. To switch on (or re-activate) SIP, repeat the above steps, except that at Step 4 use
csrutil enable
instead ofcsrutil disable
.