What process should I use for emoticons for twitch ?

Is it better to make the largest size for emoticons(112x112) with regular brush tool and sketching, or make normal sketch(around 500/600 pixels for more workspace), color it, and then resize it to 3 other sizes ?
Or maybe I should use pen tool in photoshop for crisper lines ?

I currently have problem with the general workflow for emoticons on twitch and resizing them without sacrificing too much on quality, and making them readable