Insert a newline without entering in insert mode, vim

Question

I want insert newlines in normal mode in vim using Shift-Enter and Ctrl-Enter. I try some solutions and mixing solutions from Vim Wikia - Insert newline wi

Answer 1

My alternative is using oo (resp. OO) to insert a new line under (resp. over) the current through this mapping: nmap oo ok (resp. nmap OO Oj)