Minor clarifications in staking as delegators procedures #1692

* Update staking.adoc

* codereview

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Co-authored-by: Raz Landau <[email protected]>

Author: saniksin

modules/architecture/pages/staking.adoc

@@ -320,8 +320,9 @@ a| * `amount` should be denominated in the token's base unit (e.g., FRI for STRK
 
 | Adding to a delegation pool
 | Invoke the delegation pool contract's https://github.com/starkware-libs/starknet-staking/blob/main/docs/spec.md#add_to_delegation_pool[`add_to_delegation_pool`^] function
-a| * `amount` should be denominated in FRI (i.e., 1*10^18^ = 1 STRK)
-* You must first approve the transfer of STRK tokens to the delegation pool contract by invoking the STRK contract's `approve` function
+a| * Adding to a delegation pool is only possible after entering it using `enter_delegation_pool`
+* `amount` should be denominated in FRI (i.e., 1×10^18^ = 1 STRK)
+* You must first approve the transfer of STRK tokens to the delegation pool contract by invoking the STRK contract’s `approve` function
 
 | Switching delegation pools
 | Invoke the delegation pool contract's https://github.com/starkware-libs/starknet-staking/blob/main/docs/spec.md#switch_delegation_pool[`switch_delegation_pool`^] function