This technique can be used on the Donchian channel (above), Keltner , or Bollinger bands .
1) Trending phase where price "walks" one side of the channel
2) Retest of the opposite side of the channel. If you like oscillators, they'll show a new momentum high here.
3) Failure to make new extremes in the trend direction
4) Enter on a cross of the basis (mid point of the channel) or re-touch of the channel. If you like oscillators, they'll give you a crossover entry here.
The difficulty is in #3, the right shoulder. This is a deep shoulder. Oftentimes, price doesn't move past the basis before retesting the channel wall.