Inspect the shape in parts
A common B flat major shape in GCEA tuning uses a small barre at the first fret on the first two strings, with the third string at fret two and fourth string at fret three. Start by sounding only the two barred strings. Adjust the index finger slightly until both notes ring with modest pressure. Then add the remaining notes one at a time. This reveals which contact needs work instead of treating the whole chord as one impossible grip that must be solved by squeezing harder.
Use brief attempts and full releases
Hold the shape just long enough to pluck the strings, then release the hand completely. Keep the thumb supportive and the wrist within a comfortable angle. A small rotation of the index finger may help more than extra force. If the reach or pressure causes pain, stop and consider another voicing or guidance from an experienced teacher. Practice is meant to develop coordination, not to train you to ignore discomfort. The instrument's setup can also affect how much pressure is required for clear notes.
Choose a musical entry and exit
Practice arriving at B flat from the preceding chord in the song, then leaving for the following chord. Count slowly and give the transition a fixed deadline. A chord that sounds good only after prolonged adjustment is not yet ready for a continuous strum. If needed, use a simpler arrangement while you develop the full shape separately, checking that the chosen notes still support the melody. AudioChords diagrams can identify the target pitches, but they are references rather than tests of endurance. The goal is a clear, timely B flat that fits naturally into a phrase you can repeat.