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diff --git a/README.md b/README.md
index 71f8659..5ca3c3a 100644
--- a/README.md
+++ b/README.md
@@ -9,3 +9,27 @@ Example:
 $ ./generate-hmacs.py 'igmobileotp://?action=secactivate&enc=VRUq6IoLWQRCMRITZEHtHUSWJiPwgu%2FN1BFyUHE5kxuHIEYoE3zmNTrAHeeUM5S3gzCnTy%2F%2Bdnbu%2FsjjQW%2BNEISx8C4ra8rLpxOl8E8w4KXHgjeBRgdvSzl%2BbzX5RYRrQlWgK8hsBT4pQYE0eFgW2TmRbzXu1Mu7XjKDcwsJLew32jQC2qyPLP8hljnv2rHwwsMfhQwgJUJYfctwLWWEDUFukEckaZ4O&v=1&mac=mhVL8BWKaishMa5%2B' 54998317
 {"sn":"48244-13456","ac":"1745-7712-6942-8698","policy":"{\"allowUnsecured\":\"false\",\"trustedExecution\":\"NOT_ALLOWED\"}","regurl":"myid.umc.edu\/igst"}
 ```
+
+# generate-otp.py
+Once you have the required information from a QR code, you can combine it with a "registration code" to derive the OTP secret. This registration code contains random bytes that were generated on the end-users device (their mobile phone), and are thus required to determine the OTP secret. An example way to obtain all of this information would be through email, if the user recieves a QR code in their email, then responds with their registration code.
+
+Example:
+```
+$ ./generate-otp.py 48244-13456 1745-7712-6942-8698 12211-49352
+9a8eab5ecc9fc413758a92ac223dc6a0
+
+To generate a code immediately, run:
+oathtool -v --totp=sha256 --digits=6 9a8eab5ecc9fc413758a92ac223dc6a0
+
+$ oathtool -v --totp=sha256 --digits=6 9a8eab5ecc9fc413758a92ac223dc6a0
+Hex secret: 9a8eab5ecc9fc413758a92ac223dc6a0
+Base32 secret: TKHKWXWMT7CBG5MKSKWCEPOGUA======
+Digits: 6
+Window size: 0
+Step size (seconds): 30
+Start time: 1970-01-01 00:00:00 UTC (0)
+Current time: 2019-10-06 08:50:31 UTC (1570351831)
+Counter: 0x31EB8E5 (52345061)
+
+814835
+```