What you are asking now is slightly different than what the thread title asks.
If you have a wavefunction and you want to show that it is normalized, you just need to perform the indicated integration and show that it is, indeed, equal to 1.
If you have a wavefunction that you need to normalize, you need to introduce a normalization factor to the wavefunction, often labeled "N", and then solve the equation for N.
E.g., if your (unnormalized) wavefunction is ψ, then call your normalized wavefunction Nψ. Then you need to solve the equation ∫N2ψ*ψ dτ = 1 for N. Note that if your wavefunction is already normalized, N will equal 1. Also note that I have used dτ to indicate that the dimension is not always "x", as in the case of the particle on the ring, which is integrated over angular space. Likewise, the limits of integration are not always -∞ to ∞. (It doesn't make sense, for example, to intregrate over angles ranging from -∞ to ∞. The integration in this case is usually 0 to 2π, which is the full range of angles around a circle.)
If you need help performing an integration, this is more of a math problem than anything else. You can find help here, but you have to first specify the actual wavefunction you are trying to normalize.