How do I set item permission so that only initiator and approvers see he item?
Good, just for the record, those options are
There are a couple of ways, but it could depend on your process for this item. The ootb way is to set in the list settings that the item is visible to the creator only, also enable approval required, and set a SP group of approver level permissions for the approvers.
In a more manual sense using a workflow to change permissions. You still may need two SharePoint groups for regular contributors and approvers. Once the item is created, change the permissions for contributor group to read and initiator to contribute. Commit pending changes after each.
If the approver does not need to change the item directly, but simply approve it, then they need only read access at most and their interaction with the tasks can "approve" the item and you use the Set Approval Status action to approve the item.
Where is the option to set the item to be visible to creator only?
I found it no worries
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