To change grams into moles using Avogadro's Number, just follow these simple steps:

1. Find Molar Mass: First, look for the molar mass of the substance. This is how much one mole weighs in grams (g/mol). For example, water (H₂O) has a molar mass of about 18 g/mol.

2. Calculate Moles: Next, use this formula to find the number of moles: $\text{Moles} = \frac{\text{Mass (g)}}{\text{Molar Mass (g/mol)}}$

3. Remember Avogadro's Number: Keep in mind that 1 mole is equal to $6.022 \times 10^{23}$ tiny pieces, like atoms or molecules.

So, by knowing the mass and using the molar mass, you can easily find out how many moles you have.