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: DUX.
Ducis in consilio posita est virtus militum.
Dux vivendi natura est.
Sua cuique natura est ad vivendum dux. ~ Note: This is included by André Rouillé in his anthology of Cicero's notable sententiae.
Dux vitae ratio. ~ Note: This is the Bennett family motto.
Ratione duce per totam vitam eundum est.
Qualis dux, talis miles.
Deo duce, comite Fortuna. ~ Note: This is the Palles family motto: "With God (as my) leader, and Fortune (as my) comrade."
Deo duce, comite Spe. ~ Note: As you can see by looking at this motto and the previous motto, there is a kind of formula at work here where you can add in whatever you want to the second part. Some other mottoes built on this pattern include "Deo duce, comite ferro" and "Deo duce, comite industria," etc.
Virtute duce, comite Fortuna. ~ Note: This turns the formula around in a different way: now virtue is the leader, with luck as a partner. It is one of the sayings Erasmus included in his Adagia, 4.10.47.
Dux bonus bonum reddit comitem. ~ Note: This is one of the sayings Erasmus included in his Adagia, 1.8.100. Notice how the predicate is wrapped around the verb, bonum...comitem, which leads to the very nice conjunction of bonus and bonum.
Dux atque imperator vitae mortalium animus est. ~ Note: The words are from Sallust, Bellum Iugurthinum.
Natura optima bene vivendi dux. ~ Note: Notice here that the noun dux, normally masculine, takes a feminine adjective, optima, since Nature (feminine) is the leader in question. The word vivendi, meanwhile, is a nice example of the gerund in the genitive case: dux bene viviendi, "a leader of living well" or, more idiomatically in English, "a guide to living well." The saying is found in Cicero's treatise, De Amicitia.
Turba militum sine duce, corpus est sine spiritu.
Omnes natura duce vehimur. ~ Note: This is included by André Rouillé in his anthology of Cicero's notable sententiae.
Dux femina facti.
Caecus caeco dux. ~ Note: This is one of the sayings Erasmus included in his Adagia, 1.8.40.
Deo duce, Fortuna comitante.
Dux mihi veritas. ~ Note: This is the Haggard family motto.
Deo duce, comite industria.
Melius duce leone agmen cervorum quam duce cervo grex leonum.
Naturam si sequemur ducem, numquam aberrabimus.
Formidabilior cervorum exercitus, duce leone, quam leonum, duce cervo.
Claudus eget baculo, caecus duce, pauper amico.