The notes here are taken from the actual Scala, so be warned that references to the "previous" proverb refer to its order in the Scala, not its order here. You can read more about the word at the Verbosum blog: SUM.
Esto quod esse videris. ~ Note: This saying plays on the difference between being (esto) and seeming to be (esse videris). Note also the use of the future imperative: esto. Although the future imperative forms are not commonly found in Latin prose and poetry, they are quite common in the world of Latin proverbs.
Omnia mea mecum sunt. ~ Note: The idea expressed here is that of spiritual self-reliance, where the things that are really yours are the things that are part of your inner character, the qualities that go with you wherever you go.
Non possunt primi esse omnes omni in tempore. ~ Note: The words are from Macrobius's Saturnalia, 2. Notice the elegant way "omni...tempore" wraps around its preposition!
Primus sum egomet mihi. ~ Note: You can find these words in Terence's Andria. The word "egomet" is an emphatic form of the pronoun "ego."
Quod vis videri, esto. ~ Note: This plays on the same idea as in the previous proverb: BE what you want to be, and appearances will take care of themselves!
Omnes terra sumus. ~ Note: Again, omnes (masculine plural) agrees with the implied subject of the verb: Omnes (nos) terra sumus. Here the word terra does not stand by metonymy for different human cultures, but instead for the dust of the earth from which we were made and to which we shall return.
Omnia bona mecum sunt. ~ Note: Here the word bona is being used substantively to refer to possessions, much as we also use the plural "goods" in English. Note also the special form mecum here, which is equivalent to "cum me," "with me."
Bono animo esto. ~ Note: Here you see the future imperative esto used with an ablative predicate, the so-called "ablative of description" or "ablative of quality." In English we might say: Keep a positive attitude!
Sunt quidam non re, sed nomine homines. ~ Note: Cicero
Ego meorum solus sum meus. ~ Note: You can find these words in Terence's Phormio.
Ubi sunt? ~ Note: The unexpressed subject of this verb is those who have passed on before us - where are they (now)? To learn about the poetic tradition associated with these words, see the Wikipedia article.
Ut ameris, amabilis esto. ~ Note: You can find this advice in Ovid's Art of Love, 2.
Sumus quod semper facimus. ~ Note: As often, the antecedent of the relative pronoun is not expressed: Sumus (hoc) quod semper facimus.
Non semper ea sunt quae videntur. ~ Note: Recall that the verb "videre" in the passive, as here (videntur), conveys the notion of "seeming" in English: Things are not always what they seem.
Omnes quae sua sunt, quaerunt. ~ Note: The words from the Paul's letter to the Philippians, 2. The saying is included by Polydorus in his Adagia, B368.
Forti animo esto. ~ Note: The phrase "forti animo" is in the ablative and is being used descriptively in the predicative with the future imperative esto; we might say in English "Be brave in spirit!" or "Have a brave heart!"
Homines sunt eiusdem generis. ~ Note: A genitive phrase can be used in the predicate, as here, to describe something, much like the English idiom, "People are all of the same type," i.e. we belong to the same type, the same species.
Plures sunt res quam verba. ~ Note: Note that in the previous proverb plus was being used as an adverb (plus vident), while here you have plus being used as an adjective: plures sunt res. The idea here is that language falls short of reality: we can make words and then more words, but there will always be more things than words.
Mecum mea sunt cuncta. ~ Note: These are the words spoken by Simonides in Phaedrus's version of the story about his shipwreck, 4.23.
Cuncti gens una sumus. ~ Note: Notice that the masculine plural cuncti agrees with the subject of the verb sumus: Cuncti (nos) gens una sumus.
Dei gratia sumus quod sumus. ~ Note: The English equivalent for the Latin phrase Dei gratiā would be "Thank God..." or "By the grace of God..." This is the motto of the Barking Borough of London; you can see their coat of arms here: image.
Vincenda est omnis fortuna ferendo. ~ Note: This proverb is a great exercise in the difference between the gerundive (vincenda, agrees with fortune) and the gerund (verbal noun, in the ablative, "by bearing with it, by enduring).
Dei plena sunt omnia. ~ Note: Note that the adjective plena can take a genitive complement: dei plena.
Estote parati. ~ Note: This is the famous motto of the international Boy Scout movement. This particular Latin form of the motto is the one used in Italy.
Qualis vis videri, talis esto. ~ Note: This offers a twist on the previous saying; now the idea is that you should be (esto) what you want to seem to be (vis videri). So, for example, if you want to seem wise, be wise! If you want to seem to be generous, then be generous!
Durum est omnibus placere. ~ Note: Here is another example of the nominal use of the infinitive: to please everybody is a hard (thing).
Bonus vir nemo est, nisi qui bonus est omnibus. ~ Note: The "nisi qui" is another example of how the antecedent of the relative pronoun can just be implied in the Latin: nisi (is) qui bonus est omnibus, "unless he is good to all." This one of the sayings you can find collected by Publilius Syrus.
Patientes estote ad omnes. ~ Note: The form estote is a plural future imperative, hence the plural adjective in the predicate: patientes.
Antiqua sunt optima. ~ Note: Note that the adjectives are being used substantively: antiqua, "the ancient (things)."