Don't snort somas. Oh my god please don't snort somas, I don't know how bad they burn, but the drain would make me puke nonstop, somas are the most disgusting tasting pill.
But yes, somas go GREAT with opiates. But they don't last very long.
I would pop my percs, wait 30 minutes, pop 2 somas, wait an hour, pop another soma(if you need it). If you really want to get faded you could take 3 or 4 somas but(depending on tolerance) you won't want to get out of bed. And for me opiatets are a get up and enjoy the day drug, so I dose light on the soma as to not overwhelm it.
But for some people, and even me on certain days, even just 2 somas can really knock you on your ass, while on other days I can pop 4 and barely feel it. And I don't have any tolerance, somas aren't something I really seek out I probably take them 10 times a year. So if you are small, or if you have stuff to do, maybe just start with 1, and pop 1 more every hour as needed. But I also used to have some redneck friends who didn't take pain pills but they loved to get somas and drink and they would seriously take like 20 somas in one night. And wake up with bruises from falling down the stairs repeatedly.
I like opiates+somas better than any other opi combo.
Unlike mixing benzos with opiates, which for me seem to dull the experience(but I still enjoy it), somas enhance it in every way.
In fact, I would say taking somas without any opiates is a waste. And you can talk like half as much of your opi when you've got somas.