The following design demonstrates how to use the ALTREMOTEUPDATE IP to trigger a reconfiguration of the FPGA from a pre-programmed serial flash device. It does not include any mechanism to update the flash device remotely (that is the subject of a future example, but you could use this as the foundation). Most of this is basic stuff, using the ALTREMOTEUPDATE user guide and application note AN603 as starting points.
The design and description has been targeted at the Cyclone V SoC Terasic development board fitted with EPCQ256 flash, but it could be very easily retargeted to a different board. Note that only the basic Cyclone V features have been used and none of the SoC portion has been used.
Have a look at the .ZIP file linked below for full documentation and the simple test design.