Assign a simple bass role
Choose a short progression with shapes you already know. Identify a suitable bass string for each chord rather than striking the same low string automatically. Play only that bass note on a slow, regular count. Listen for a consistent attack and relaxed thumb movement. If the bass note changes between chord shapes, practice that transition separately. A steady thumb creates a useful foundation, but it does not mean every song needs a bass attack on every beat or an alternating bass pattern.
Add one upper voice at a time
After each bass note, pluck one upper string with a finger. Keep the two events evenly spaced and repeat through the progression. Then add a second upper string if the pattern remains comfortable. Avoid learning a large sequence before you can hear how its notes fit the chord. Check that a melody note or open string does not clash in a way you did not intend. Let the picking fingers return naturally instead of pulling far away from the guitar after each note.
Let the harmony interrupt the pattern when needed
A picking pattern is a device for expressing the song, not a loop that overrides its structure. If a chord changes halfway through the pattern, move at the correct beat even if you have not completed the usual sequence. Practice the boundary with a simpler pair of plucks, then rebuild the fuller pattern around it. AudioChords can help you follow the progression, but listening determines the placement and character of your part. Finish by singing or humming over the accompaniment. If you cannot keep the phrase and thumb pulse together, reduce the upper-note activity until the two layers cooperate.