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Might look something like this: http://www.lifeformz.com/cgi-bin/idea/idea.fcgi Note that the output is grammatically correct (more or less). The more constraints you put on the text you want, the lower your ciphertext bandwidth will be. But let's say there are 20,000 words in your dictionary, the base 2 log of 20,000 is 14. That means you get 14 bits for each word you choose. If you need to send 50 bits of data, you will need to send 4 of those words chosen from the list (4 words will allow you to send 57 bits). The recipient will take each word and look up its ordinal value in the list and convert that to binary. If it is word number 9,876 your 14 bits are 10011010010100. That is the "word salad" solution and it would draw suspicion by an adversary.

If you want grammatically correct text like that generator, then each word you choose is limited to an adjective, noun, verb, article, etc depending on the position in the sentence. Since the first word might be an article, that will only be 1 binary bit at best ("the" or "a"). Sometimes the article is constrained. The next word might be an adjective, if there are 5,000 adjectives that is 12 bits. Then another adjective or maybe a noun with 10,000 choices for the noun (13 bits).

You can see that grammatically correct or plausible phrases are more and more limiting so you need to send more words. Another factor to consider is that the adversary may figure out the encoding, so it is probably not good to have a fixed dictionary between the sender and receiver. That means the sender will need to send even more words to tell the receiver how to set up the dictionary.

The bottom line is that the generator I linked above is probably well over 50 bits, and would work.