There were no mention in NOL's document on SRS holder ( Supplementary Retirement Scheme).

So first thing you must do is to call your SRS account operator ( one the the banks that has your SRS account) and ask for the procedure.

I think it is the same as CPFOA procedure where agent bank must be informed to accept rights on your behalf.

Below is copy from CCT rights , one portions related to SRS for reference reading ONLY.

(B) Use of SRS Funds
Unitholders with SRS accounts must use, subject to applicable SRS rules and regulations, monies standing to the credit of their respective SRS accounts to pay for the acceptance of their provisional allotments of Rights Units and (if applicable) application for Excess Rights Units.
Such Unitholders who wish to accept their provisional allotments of Rights Units and (if applicable) apply for Excess Rights Units using SRS monies, must instruct the relevant banks in which they hold their SRS accounts to accept their provisional allotments of Rights Units and (if applicable) apply for Excess Rights Units on their behalf in accordance with this Offer Information Statement. Such Unitholders who have insufficient funds in their SRS accounts may, subject to the SRS contribution cap, deposit cash into their SRS accounts with thoir approved banks to enable them to subscribe for their provisional allotments of Rights Units and (If applicable) apply for Excess Rights Units. SRS monies may not, however, be used for the purchase of the provisional allotments of Rights Units directly from the market.

In a way, it's just like playing an option... 

At least one can have a taste of trading options without trading options... hehehe...