Capital Gains tax on SIP shares

Do I have to transfer shares from company scheme directly to a Stocks and Shares ISA in order to avoid CGT or can I cash them in and then transfer the proceeds into the Stocks and Shares ISA to avoid the CGT so long as I do this within 90 days. It’s not clear on the HMRC website how to do this.

Hi Mark Fox,
Its the actual shares you need to transfer too avoid CGT.
Thank you.