Jumping up on people and counters

Hi. I’ve had our puppy for a little over a month now. Unsure of exact breed (waiting on Embark) but they said hound/golden retriever mix. She’s a little over 3 months old. She’s an absolute ROCKSTAR with just about everything. The only trouble we’re having with her is jumping up on people and counters. She’s going to be a big dog so I’d like to get this under control. What has worked for you?