THE COMMANDERS STRATEGY:

Estrid, The Masked's 2nd ability can enchant ALL of your permanents with a Totem armor Aura.
Do so to protect the most relevant cards on the board with Totem armor. Also, the Masks you play are enchantments, which will trigger the abilites of most of your other cards in play (e.g. card draw, +1/+1 buffs)

In addition to that, Estrid's 1st ability untaps each enchanted permanent.
Do so to even untap lands, you previously enchanted with her 2nd ability or with other Auras in you deck like Fertile Ground.

Her 3rd ability is used rather rarely, but if you manage to get her loyalty counters up that high, you can get back all your enchantments from your graveyard (including Auras) and bring them back to the battlefield.

THE DECKS STRATEGY:

A lot of carddraw and cards that trigger sweet, versatile stuff, as you play enchantments.
Enchantments surive most board wipes, due to most board wipes being creature wipes.
If it's not a back-to-hand board wipe like Cyclonic Rift, you're pretty safe thanks to the totem armor Estrid provides or with Heroic Intervention.

When you're playing in a multiplayer party try to grow in the shades and let your commander build up a safeline of Mask-enchantments (plus Propaganda and Ghostly Prison or Sphere of Safety).

Get back your most valuable cards in the graveyard with Retether, Creeping Renaissance, Bruna Light of the Alabaster.

When feeling confident attack with flying thanks to Archetype of Imagination or with a bunch of Aura cards that give your creatures trample.