Deployment Through WorkBench

1.Create the "package.xml"  which needs to be deployed,If you already created changeset and here is the link to generate "package.xml" from change set Refer

2.Login to the workbench to retrieve the components.[Source Sandbox]

3.Login to the workbench to deploy the components.[Target Sandbox]

Note : 1.Use the 'Check Only' option to validate this deployment without making changes.
If validation is success then can deploy
2.The zip file should be in this folder structure Package_Name\unpackaged\Files