You can load the SID waypoints but as in the realty after TO the ATC radar can give you some vectors due to the traffic.When the ATC will instruct you to resume the normal navigation you can resume it as you like.By radio instrument with the autopilot or manually or by autopilot and INS.If you 'll choose by Autopilot and the INS you have two possibilities:
1-Pushing WYPT-CHG 0-X INSERT if the next waypoint isn't far and your navigation off track will be short.
2- If the next waypoint is quite far and the navigation off track will be too long before to couple the INS with the autopilot you have to select XTK/TKE  and steer properly the plane to reduce by the HDG selector the XTK/TKE to zero or near to zero. At this point the INS can be coupled with Autopilot and the navigation will be conducted by the INS.