Bewear is perhaps one of the most annoying pokes in gen 7; not only does it get a good attack stat, but between 120/80/60 defenses and the Fluffy ability, it can eat a few hits. Its STABs are difficult to resist except for Ghosts, and Bewear has Shadow Claw and Payback for those, plus several other great coverage options. The only things I'd argue Bewear lacks are speed and Drain Punch, otherwise it's pretty solid.
So far I've mostly seen suggestions for bulky attacker sets, which I've sort of lumped into one because they're somewhat similar:
The Bewear Necessities
Item: Choice Band / Assault Vest
Ability: Fluffy
Evs/Nature: 92 HP / 252 Atk / 164 Spe, Adamant
- Superpower / Hammer Arm
- Return
- Ice Punch
- Shadow Claw / Earthquake
This set is pretty much what you'd expect. STABs, Ice Punch for anything 4x weak to Ice (Ground types in particular are a problem b/c Fluffy doesn't stop EQ), and either Shadow Claw for Ghosts or EQ for broader coverage. The EVs and nature maximize attack, outspeed uninvested base 80 speed, and place the remainder in bulk. Ability is Fluffy, period. Item is up to you, being slow and Choice-locked is never fun but then Assault Vest isn't as good as it would be with Drain Punch; Bewear may not last long-term. Superpower is probably the better STAB here due to higher BP and since the defense drop doesn't kill Bewear every time, but Bewear can stay in longer spamming Hammer Arm if being slow(er) doesn't kill you.
OOs for this set include: Payback (in conjunction with Hammer Arm only), ThunderPunch (good for bulky Water-types, good synergy w/ Ice Punch), and Leftovers.