A typical capacitor connection in parallel will look like the one I draw below:

"Parallel" means the capacitors are wired together directly at one plate and also wired directly at the other plate, and therefore the "V" (Potential Difference) is applied acrossed the two groups of wired-together plates. The total charge q stored on the capacitors is the sum of the charges stored on all the capacitors. Hense we can regard capacitors connected in parallel as a capacitor that has the same total charge q of all these capacitors and same potential difference V.

If the charge of C1 is q1=C1*V, and for C2, q2=C2*V and for C3, q3=C3*V, then q total=q1+q2+q3=(C1+C2+C3)*V

From that we can say C total = (q total) / V = C1+C2+C3

If there are n capacitors connected in parallel, then: C total = `sum_(i=1)^n` C _i

Hope this is useful.