1993 Chevy S-10 not getting spark

Electrical problem
1993 Chevy S-10 6 cyl Automatic 88000 miles

my truck turns on fine that after I use it a little and turn it off it wont start back up. The cap a rotor were bad weeks ago I replaced worked fine than I started having this problem I replaced the alternator because of the voltage regulator not that. Replaced the ignition coil not that replaced the fuel relay not that I checked for spark at the plug and im not getting any what else should I check and how I have a multi meter