First download MathWallet:https://www.mathwallet.org
Switch to NEAR wallet ,open DApp – NEAR Staking Tool
Add staking
Click +stake
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Select the validator, CURRENT means the active account, and the commission rate is the commission charged by the validator, which will be deducted from the income
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Click Delegate
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Choose active/lockup account
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Unstake
Click corresponding delegation
Click Unstake
Enter the unstake amount and click unstake
Note: It takes about two days for the staking assets to be released. After the end of the lock-up period, the unstaked asset will become cashable asset.