Find a wolf in a forest, taiga, snowy taiga, old growth pine taiga, or grove biome
Get bones from skeletons
Hold the bones in your hand
Right-click or use the bone on the wolf
Keep feeding bones until hearts appear
The wolf is now tamed and becomes your dog
Use a lead to move it if needed
Right-click or use it on the wolf to make it sit or stand
Feed it meat to heal it if it is injured