it's hard to tell cuz it all depence on the situation,
you should work on your speed during training though.

things you might want to give a shot are
moving in angles so your opost needs to adjust to your position, and when he is adjusting you throw in your punches.

when he throws a jab you slip to your right, adjusting your right hand in defence since there can't come a punch from that side and in the same movement as you slip you throw your lefthook under his jab, and you can folow up with a right cross. (hard to explain and doesn't sound safe) but try this a couple of times in your sparring to find out how it is dun, and you'll see it is safe.

if he is a SP and throws a right jab, you can make a (small) step with your left foot, and plant it outside his front foot, you'll notice that your head also moves outside of his punch, so your safe.
now as you make that step you throw a right mix of hook and uppercut (go diagonal) upwards and land on the chin.

(you can folow this up with a left hook)

practice this first for a while so you'll find a safe way use it.

hope this helps