I also use jiffy sometimes, the coco ones, so I place it directly into the soil from it also because roots have already formed inside it, if you try to break it open you may damage the roots, might also stunt growth etc .
So make a hole the size of your jiffy, dump your jiffy inside and lightly cover the jiffy with soil and around it so no light gets in - basically after it is in possition cover the hole. make the soil damp but not soaking wet, keep them at around 60% humidity , don't drop the water directly on it, but close to the stem and around it , i'd suggest water early morning or late evening when the light isn't strong. Are the seeds Autos?