「拜」was originally「𢳎」, comprised of「手・扌」and「𠦪」.
「𠦪」(please read this in both meaning and sound as「禱」) depicts flowery adornments used in dances and religious prayer/rituals.
商
甲

佚32
合集1439西周
金

番生簋蓋
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簡

日甲61背
篆

說文解字
今
楷

The combination of「手」(hand) and「𠦪」(flowery adornments used in dances and religious prayer/rituals) indicated the meaning to conduct obeisance.
西周
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沈子它簋蓋
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簡

睡・秦153
In the character「𢳎」, the bottom part of「𠦪」was sometimes corrupted into something that looked like「手」.
秦
簡

日甲166
Similarly, the top part of「𠦪」, which is「卉」, was sometimes removed. This leads on to the modern form of「拜」.
東漢
隸

鄭固碑
今
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