Along side a sofa is good, or a dresser, counter, or washing machine (as were good suggestions earlier). Something about hip or waist height is ideal. Doorways are BAD--if you tip, you can bounce between like a pinball. Get used to having the support on the same side--like clipping in, always use the same side--I like it on the side I clip in & out of when at stops. That way I get the bike on the roller, clip in my right shoe, leaning against the dresser on my left side, get on the bike, start to spin and clip in. I always have it in the big chain ring--not a super hard gear, but you need decent resistance and speed to feel the weight/balance into the wheels. Lean your hand onto the support when you need to, and to stop. With practice you should be able to work w/ a water bottle as you would on the road... but until then, don't be afraid to gently lean on the support as needed for rest/water breaks. I also made a "sweat strap" to protect my top tube from my dripping sweat, and also keep a towel on the floor under the rollers. Without the wind from being on the road, you quickly learn just how much you can sweat!