What are the (resultant) tones in those sentences, where all the words in isolation have 3rd tone?
Reading tone shandhi rules on Wikipedia, there is no explanation about tree or four single-syllable words with 3rd tones.
Looking at 我很好 this falls into the "When there are three 3rd tones in a row"
The 我 is one syllable so it falls into this part:
If the first word is one syllable, and the second word is two syllables, the first syllable becomes half-3rd tone (˨˩), the second syllable becomes 2nd tone, and the last syllable stays 3rd tone
For this 我也很好 this is logically split like this (我也) and (很好) which would result in two lots of
the first syllable becomes 2nd tone (˧˥), and the second syllable becomes a half-3rd tone (˨˩)
At least that's what the rules say. As per my comment above, don't bother memorizing this. It is more likely an incidental phenomenon as a result of regular use of the language. In other words, you will pick it up by learning to speak it fluently rather than trying to learn it from paper.
There's no fixed answer how tone sandhi happens when three or more 3rd tone come together. It is still an active research area for linguists. It depends on grammar, speaking rate, and many other things.
However, in normal speech, no two 3rd tone would come together (in a word), the first one must change. It seems to be still under debate (among linguists) what would happen when the two continuous 3rd tone are not in one phrase.
So you can follow @xiohouzi79's advice, "don't bother to memorizing this".