Multiply the molarity with number of Hydrogen ion , Hydroxyl ion for acid and base and for redox reaction multiply with the number of electron gain or lose.
Molarity is simply number of moles of solutes in 1 litre of the solution... Number of moles can be calculated by using weight of solutes to the molecular weight of solutes... Normality on the other hand is number of equivalent weight of the solute in 1 litre of the solution...Here number of equivalent can be calculated by using ratio of molecular weight of the solute divided by its valency...For example 1 normal solution of KCl will be equal to 1 molar solution of KCl as valancy of K+ is 1 while in case of CaCO3, 1 molar CaCO3 will be equal to 2 normal of CaCO3...It means multiplying valency with the molarity of the solution, one can estimate normality...