I would recommend, for recreational use, 1 mg lorazepam if you have no benzo tolerance. This dose will most likely bring about a good deal of anxiolysis (anxiety-relief), a sense of being somewhat "calmer" or "more tranquil", relaxation of the body (in the muscles), possible sleepiness, somewhat impaired and slowed cognition and judgment, somewhat disinhibited behavior, a possible sense of "floatiness" or "lightness", some (not likely troublesome) memory disturbance and forgetfulness, and slower reflexes, on the whole. There may be some sedation, but a bit of excitation due to disinhibition is possible, too.
I suggest 1 mg because it is a good starting dose for lorazepam - lorazepam tends to be more subtle with respect to its actual effects than other benzos for a lot of users, and can cause issues for this reason (it might not seem like a lot, but you can only expect so much from lorazepam, or any benzo). DO NOT mix with alcohol, or any other CNS depressant drugs unless you are already quite dependent to them - the mix is potentially very dangerous, especially for novice to such drugs.
Really, if you take 1 mg lorazepam without benzo tolerance, expect subtle but very real effects including relaxation and calming. Taking more would not be a good idea on account of the possibility of very poor judgment and/or amnesia.