Use "Torrential Tribute" on an opponent's monster while you have a face-up "Sacred Phoenix of Nephthys" to destroy all the monsters on the field. When your opponent's turn ends and you get to your Standby Phase "Nephthys" will be summoned back by her own effect and wipe your opponent's Spell and Trap Zone, effectively leaving them open while you have a monster with 2400 ATK on your side of the field. You will also have your Normal Summon that turn.
Equipping this card with "Mist Body" will prevent destruction by battle, meaning your opponent's only option for destroying it will be with an effect, triggering Nephthys' effect. Try not to let your "Mist Body" be destroyed, though.
A combo that can be repeated as many times as desired is Tribute summoning "Dark Dust Spirit" with "Treeborn Frog" while "Sacred Phoenix of Nephthys" is on the field. "Dark Dust Spirit" destroys all monsters, activating "Sacred Phoenix of Nephthys", which will destroy all Spells and Traps during your next standby phase, and finally, allow "Treeborn Frog" to return to the field and be sacrificed once again for "Dark Dust Spirit". Alternatively, you can use "Level Eater" instead of "Treeborn Frog".
Additionally, to help not leave yourself open once "Dark Dust Spirit" returns to your hand, having an "Abyssal Kingshark" on the field will help you keep a field advantage.
Use self-recycling Equip Spell cards, such as "Horn of the Unicorn", in conjunction with this card to make up for its somewhat low (for its level) ATK. When it is destroyed by a card effect, this card will come back to the field, and you will be able to re-equip it.
"Dark Coffin" and "Statue of the Wicked" are two Traps that work well to your benefit when destroyed by card effects. "Blast with Chain" can also work--if you control no other monsters, you can even chain that card to the activation of the Phoenix's destroying effect when it revives itself.
This card has several uses with "Widespread Dud". Activate "Widespread Dud" and target "Sacred Phoenix of Nephthys" and an opponent's monster. You can also target one of your own monsters that is going to leave the field to trigger "Nephthys's" effect. If your "Nephthys" revives while you have a facedown "Widespread Dud", you can activate it to destroy two of your opponent's monsters. If "Nephthys" is attacked by a stronger monster, you can activate a Trap that will destroy "Nephthys" and chain "Widespread Dud" to it, targeting the stronger monster.
Use this card in a "Gemini Deck". If this card is equipped with "Symbols of Duty" you can use "Evocator Chevalier" to destroy "Symbols of Duty". This will destroy one card your opponent controls, and then next turn destroys all Spell and Trap Cards.
Activate "The Seal of Orichalcos" while this card is on the field, if you Special Summoned it by "Hand of Nephthys". The Seal of Orichalcos will destroy "Sacred Phoenix of Nephthys", but it will be Special Summoned back next turn by it's effect, destroying all Spells and Traps on the field, except "The Seal of Orichalcos", because it can't be destroyed by card effects once per turn. Also, "The Seal of Orichalcos" will give "Sacred Phoenix of Nephthys" a 500 attack boost, making its ATK 2900.
Utilizing two copies of "Fire King High Avatar Garunix" and 1 copy of this card, one can destroy every monster and Spell/Trap Card on the field, and one would be left with one "Fire King High Avatar Garunix" standing alone. This is accomplished by having 1 "Fire King High Avatar Garunix" on the field and 1 "Fire King High Avatar Garunix" in the graveyard, with its effect primed, as well as a copy of this card. Then, bring back the "Sacred Phoenix of Nephthys", to destroy all Spells and Traps. Then bring back the "Fire King High Avatar Garunix" to destroy all other monsters, including the first "Fire King High Avatar Garunix" and the "Sacred Phoenix of Nephthys", setting up for one's next Standby Phase.
One can also utilize monsters such as "Ultimate Axon Kicker" that cannot be destroyed by card effects to maintain more field presence.
Another option is to use cards such as "Yubel" that need to be destroyed to function.
Use this card with "Stardust Dragon" to choose when you want to use the destruction effect. When this card is summoned by its own effect, it gets its destruction effect, you can Tribute "Stardust Dragon", negating the destruction and destroy this card by an effect, allowing you to repeat this until you want to use the destruction. It will mean you have 2 less monsters but you can choose when the effect will activate.