There is a built in method for this:
byte[] data = { 1, 2, 4, 8, 16, 32 };
string hex = BitConverter.ToString(data);
Result: 01-02-04-08-10-20
If you want it without the dashes, just remove them:
string hex = BitConverter.ToString(data).Replace("-", string.Empty);
Result: 010204081020
If you want a more compact representation, you can use Base64:
string base64 = Convert.ToBase64String(data);
Result: AQIECBAg
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