In my closed guard, I like to sit up and try a sloppy guillotine then fall back with it. When they bring their hand up on that side to pull your hand away from their throat, throw that leg around their arm and up onto their neck for the triangle position.
i do it braulio estima style, deep collar grip threaten collar chokes and then they defend i try the armbar and if they pull their elbow in shoot the hips up and lock the triangle or collar choke with the legs (deep collar grip with the legs triangled the opposite way of a regular triangle)
I mostly use the triangle from mount. Sneak the leg in, and when they try to make me lose mount, i close it.
From my back i usually can only make triangles after a failed/fainted armbar.