There isnt much that can be done if the seeds are already forming. Just let the buds ripen as normal, and treat it like any seeded commercial bud and shuck out the seeds before smoking. You never know...those seeds might be holy grail of strains. More likely they will also be hermies too, and poor quality, but its always good to think positive.
If seeds are forming now you can wash it gently with plain water to kill all the remaining pollen that could still produce a lot seeds but be sure to dry up the plants after to prevent mold. If seeds are just formed ther'snt much to do try to harvest as soon as you can/like preventing other seeds to come