1996 Replacement Keyless entry

I just bought a 96 toyota avalon with 156k miles and it did not come with OEM key or keyless remote. I've been doing reserach to find out which keyless replacement remote i need to get. I assume its the manufacture keyless remote and i have to locate the light failure sensor in the trunk. I can't seem to find it, and when i do find it and have the keyless entry remote how do i program the remote to my car?