Very easy, if it makes you puke, that means you too TOO MUCH.
So, to prevent the vomiting, just don't take too much.
In an opiate naive individual, buprenorphine is ridiculously potent. I would take 250ug (1/32nd of an 8mg pill/strip) if you have no opiate tolerance. If you have an opiate tolerance, you'll want to take more, of course - but start low, because bupe has a long halflife, and you could be sick for days if you take too much (plus, taking too much like that will raise your opiate tolerance that much more than a low dose, despite not producing enjoyable effects)
Some diphenhydramine (benadryl etc) would likely be a good thing to take to reduce nausea as well.
I would not take a benzo with bupe until you are familiar with the effects of bupe and can choose an appropriate dose, since a benzo plus an excessive dose of bupe could be dangerous.