A Healer Pre-entry holster is based on each Healer's playstyle. Avoid putting B2 actions ahead of time, instead allocate one slot to be Lost Seraph Strike or Lost Chainspell. Both of these actions can be carried from start to finish without renewing any charges.
Note: Bring either Lost Spellforge or Lost Steelsting.
These are some useful tips in preparing your Holster as a Healer.
Mandatory: Allocate as many Lost Arises as Possible.
Mandatory: Bring Lost Spellforge / Steelsting, based on your assignment on the spreadsheet.
Decide between Lost Reflect or Light Curtain. (refer FAQ-healer for more info)
Mandatory: Have Resistance Reraiser (approx 3 ~ 4). These are items so have them slotted into your hotbar.
Remaining capacity to bring either the following:
Additional Resistance Reraiser
Resistance Ether Kit (For Seraph Strikes)