Setting up a multisig wallet with sparrow.

If you are active here on the forum you must have come across MULTISIG a number of times. Multisig is just the short form of multisignature which is a security practice that allows you to use two or more private keys to authorize transactions. Instead of a single key to control the funds, control us divided between devices or people.
Here is a simple tutorial on how to setup multisig using sparrow wallet:

Prerequisites

Sparrow Wallet downloaded from sparrowwallet.com (verify PGP signature).

Three Signers: Ideally hardware wallets from different manufacturers (e.g., Coldcard, Blockstream Jade, BitBox02, Foundation Passport, Trezor, Keystone, Ledger).

Backup Materials: Steel plates or a notebook or a paper card for seed words offline storageand flash drives/printouts for the Output Descriptor.

Step 1: Create the Multisig Policy in Sparrow

Open Sparrow and select File > New Wallet

Name your wallet (e.g. Vault-2of3) and click Create Wallet.

Configure the Settings screen:

Policy Type: Multi Signature
Script Type: Native SegWit (P2WSH) (Addresses will start with bc1q... — offers the lowest transaction fees and universal hardware compatibility).
Cosigners: 3
Signatures Required: 2

Step 2: Import Keystores (Signers)
You will see three tabs: Keystore 1, Keystore 2, and Keystore 3. You must import the public key (xpub / Zpub) and master fingerprint for each device:

Option A: Connected Hardware Wallet (USB)
Plug in and unlock your device (BitBox02, Jade, Trezor, Ledger).
Click Connected Hardware Wallet > Scan... > Import Keystore.

Option B: Airgapped via MicroSD (Coldcard)
On Coldcard: Go to Advanced/Tools > Export Wallet > Sparrow Wallet and save to MicroSD.
In Sparrow: Click Airgapped Hardware Wallet > Coldcard > Import File... and select the .json file.

Option C: Airgapped via QR Code (Jade / Keystone / Passport)
On the device, select Export Multisig XPUB / Account via QR.
In Sparrow: Click Airgapped Hardware Wallet > Scan QR and show the device screen to your computer's webcam.

Repeat this for Keystore 2 and Keystore 3 using your remaining devices.
Once all 3 are imported, click Apply and set a strong wallet password.

Step 3: Register the Multisig on Each Hardware Signer
this is very important because If your hardware signer does not know the full multisig policy (the XPUBs of the other cosigners), it cannot verify that the change address belongs back to you when you spend. A compromised computer could redirect change to an attacker without your hardware device alerting you.

Coldcard: In Sparrow, go to Settings > Export > Coldcard Multisig, save coldcard-export.txt to the MicroSD card, and on Coldcard go to Settings > Multisig Wallets > Import from SD.
Blockstream Jade / Keystone / Passport: In Sparrow, click Settings > Export > Output Descriptor QR (or BSMS file) and scan/import it into the device under Register Multisig.
BitBox02 / Ledger: Sparrow will automatically prompt you to confirm the multisig registration on the hardware screen when connected.

Step 4: Back Up the Output Descriptor
In single-sig, your 12 or 24 seed words are enough to restore your wallet. In multisig, seed words alone cannot restore your funds

You must backup:
The Seed Phrases for each of your hardware devices (preferably stored in separate locations).
The Output Descriptor / BSMS File (contains all derivation paths, XPUBs, and the threshold rule).

To export in Sparrow:
Go to Settings > Export.
Export both Sparrow format (.json) and BSMS / Output Descriptor (.txt).
Store a copy of this descriptor file (or printed QR code) alongside every seed phrase backup.

Step 5: Receiving Bitcoin
Click the Receive tab.
A new bc1q... multisig address will be displayed.
Click the Hardware Device Icon next to the address to display and verify the address directly on your hardware screen before depositing.

Step 6: Spending via PSBT (Partially Signed Bitcoin Transaction)
Construct TX: Go to the Send tab, enter the destination address, amount, and fee rate, then click Create Transaction.
Finalize: Review the transaction graph and fee, then click Finalize Transaction for Signing.
Sign with Key 1:
USB: Click Sign next to Keystore 1 and approve on your device.
MicroSD: Click Save PSBT, sign on Coldcard, and click Load PSBT in Sparrow.
QR Code: Click Show QR, scan with Jade/Keystone, sign, and scan the signed QR back into Sparrow.
Sparrow will show: Signatures: 1 / 2.
Sign with Key 2: Repeat the signing process for Keystore 2. Sparrow will update to Signatures: 2 / 2 (Quorum met).
Broadcast: Click the blue Broadcast Transaction button to send it to the network.

Before depositing life savings into your new multisig wallet:
Deposit a small test amount (~$10–$20 worth of sats).
Close and delete the wallet from Sparrow.
Restore the wallet from scratch using your Output Descriptor and your keystores to ensure that the recovery works.
Perform a test spend signing with Key 1 + Key 2.
Perform a second test spend signing with Key 1 + Key 3 if you have a third key
Once full recovery and signing combinations are proven, you can safely use the wallet for long-term cold storage.

I really hope this helps someone who has been wanting to setup a multisig wallet.