First download MathWallet：https://www.mathwallet.org
Note：IOS user please download TestFlight version ( How to install MathWallet iOS TestFlight version?)
Switch to NEAR wallet ，open DApp – NEAR Staking Tool
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
Choose active/lockup account
Click corresponding delegation
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.