“Bellona’s themes are protection, victory, communication and strength. Her symbols are swords (or athame) and spears. She who kindles the fire of the sun and the fire in the bellies of warriors, Bellona is both a mother and a battle Goddess, being the female equivalent of Mars with a distinct diplomatic twist. Those who call upon Bellona receive strategy, tactfulness and a keen sense of how to handle explosive situations effectively.
In ancient Rome, today was known as Tubilustrium in which Romans spent the day ritually cleansing their trumpets for battle and honoring the people who make the trumpets. In this part of the world, a horn not only signaled a charge but invoked the Goddess’s attention. So, for what personal battle(s) do you need to sound Bellona’s horn today? Find a horn with which to do just that (perhaps a kazoo or a piece of construction paper rolled to look like a megaphone). Shout your battle plans to Bellona so She can respond with all Her resources to help you.
If you use a sword, athame (sacred knife) or wand in magic, today is an excellent time to take out that tool and invoke Bellona’s blessing upon it. Oil and sharpen the blade, polish the wood, then hold it in your hand as if it were a weapon, say,
‘Bellona, see this implement of magic, which as any, has two edges – for boon and bane. May only goodness flow through this tool, and may I ever remain aware of the responsibility for its use. So be it.'”
(Patricia Telesco, “365 Goddess: a daily guide to the magic and inspiration of the goddess”.)
According to Patricia Monaghan, “Often described as a feminine shadow of the god Mars, Bellona was actually much more, for Her domain included the entire arena of conflict, diplomatic as well as military. Ever Her name shows Her importance, for the Latin word for war, bellum, derives from Her name.
In the temple of this serpent-haired Goddess who bore a bloody lash, the Romans began and ended their military campaigns. Before Bellona’s temple, Her priests began war by raising a ceremonial spear and hurling it into a section of ground that symbolized enemy territory. When the war was finished, it was in Bellona’s temple that the Senate determined the best reward for the victorious generals. And during peacetime, the Senate used Bellona’s temple to receive the ambassadors of countries in conflict with Rome.
When Roman divinities began to be identified with those of the countries Rome conquered, Bellona found Herself assimilating the Cappadocian Goddess Mah, a late form of the Sumerian Mami. Both symbolized territorial sovereignty and both represented the armed conflict necessary to defend claims to rulership. The Roman Goddess was called Mah-Bellona in the later days of the Roman Empire. She was associated as well with Erinys (Furies) and with Discordia.” (p. 68)
Thalia Took has this to say about Bellona: “Bellona is the Roman Goddess of War, closely associated with Mars, the Roman War-God. She is invariably His companion, although She can be called His wife, daughter, sister, or charioteer. Her origins are probably Sabine (an ancient tribe from the lands north-east of Rome), and the Claudii, a Sabine family, are credited with instituting Her worship. Her temple was built in the Campus Martius, the low-lying field by the Tiber consecrated to Mars, located outside of the city walls. The area around Her temple was considered to symbolize foreign soil, and there the Senate met with ambassadors, received victorious generals, and there war was officially declared. Besides Her temple was the columna bellica, or war column, representing the boundary of Rome. To declare war a javelin was thrown over the column by one of the fetialis, a type of priest involved in diplomacy, and this act symbolized the attack on a foreign land.
Bellona was believed to inspire a warlike frenzy and enthusiasm (much like that of the Norse berserkers), and Her earliest sacrifices are said to have been human. The worship of the Anatolian Goddess Ma, who is of a similarly martial nature, was brought to Rome by Sulla where She was assimilated to Bellona, and called Ma-Bellona. Her priests were called the Bellonarii, and during the rites to Ma-Bellona they mutilated their own arms and legs, collecting the blood to either drink or offer to the Goddess to invoke the war fury. In later times this act was toned down to become merely symbolic. These rites took place on the 24th of March and so accordingly that day was called the dies sanguinis (“day of blood”).
Bellona had several shrines and temples in Rome, though most are known only from inscriptions referencing them, as well as a temple in Ostia, the port city of Rome. In 48 BCE, a shrine to Ma-Bellona was accidentally destroyed when the demolition of the temples of Isis and Serapis in Rome was undertaken; within the ruins of the shrine were found jars containing human flesh, said to be evidence of the orgiastic nature of Ma-Bellona’s worship and to link it with the Egyptian religions, though how I’m not sure, unless perhaps the jars were functioning as the so-called canopic jars that housed the internal organs of the dead in Egyptian funerary practice.
Bellona is usually shown in a plumed helmet and armor, armed with sword and spear and carrying a shield; sometimes She carries a torch with a blood-red flame. She is described as loud and active, barking orders or war-cries, Her weapons clanging as She runs. She is credited with inspiring violence, starting wars, and goading soldiers into battle; Virgil described Her as carrying a bloodstained scourge or whip. She was believed to make wars and battles go well for those who invoked Her. Her name comes from the Latin for war, bellum, and Her original feast day was June the 3rd.
She is identified with Nerio and Vacum (both Goddesses of Sabine origin, like Bellona). Ma, or Ma-Bellona is a Goddess of Cappadocian origin (a region in Anatolia, modern Turkey) who was identified with the Italian Bellona, and for whom a separate temple was built in Rome.
Also called: Bellola, Duellona (from an earlier Latin word for war, duellum); Bellona Pulvinensis; Bellona Insulensis, from a shrine on the Tiber island. She is described as ‘dark Bellona, with bloody hand’, by Publius Statius (court poet to the Emperor Diocletian). Dollars to donuts She is the namesake of the ever-grouchy and rather hostile B’Elanna Torres from (Star Trek) Voyager.” 
Monaghan, Patricia. The New Book of Goddesses and Heroines, “Bellona”.
Took, Thalia. The Obscure Goddess Online Dictionary, “Bellona“.
Bar, Tala. Bewildering Stories, “Goddesses of War“.
Gangale, Thomas. The Temple of Bellona, “Bellona“.
Roman Myth Index, “Bellona“.
Theoi Greek Mythology, “ENYO: Greek Goddess of War“.
Wikipedia, “Bellona (goddess)“
Wikipedia, “Temple of Bellona (Rome)“.