Hydrangeas are usually not a re-blooming plant.  Do you have the name of the plant you have?  Otherwise, you simply cut off the blooms when they turn brown or, if they are a hardy hydrangea planted in the ground, they can stay on the shrub for winter interest and cut back in the early spring.  Gerber daisies are annuals here.  Once a bloom fades, cut the stem all the way back to encourage new blooms.  They need to be removed or it will stop producing new blooms.

I still need to know the variety of hydrangea you have.  Care depends on that.  You should get more leaves.  Please respond with the name from the label.

I don't know where or from whom you got your hydrangea but it is important for you to know to properly care for it.  If it is not hardy in our zone, you will need to bring it inside and care for it during the winter or let it freeze outside and toss it.