Space map key to switch to insert mode

I am trying to display my space to force Vim to switch to insert mode from normal mode.

The reason I want to do this is because sometimes I forget that I am in normal mode and start typing as if I were in insert mode. When I press the space bar between or even at the beginning of the page, it moves down and something or other types because of the possibility of pressing aor iin what I just typed.

Therefore, to avoid this, I want my space bar to insert a mode from normal mode when we click ito do this.

I tried the following:

map space :i
map <space> :i

But they do not seem to work.