The first thing you need to know is that there are so many ways to lace shoes; it all depends on which of these ways you're familiar with.
However, the one you are to learn is the simplest method of them all, and I hope it helps.
1. Place your shoe in front of you as though you are about to wear it.
2. Check your shoe very well; you should notice different opposite facing holes. Start with the first opposite facing holes and insert the lace to pass through the two holes. At this point, the lace has somehow been divided into two parts but make sure they are of the same length.
3. Put the end of the right lace through one of the next second opposite facing holes in a diagonal manner. Also, put the left lace of the first opposite facing holes through the second hole of the second opposite facing holes in a diagonal manner.
4. Continue this process the same way we did in step 3 till you get to the last opposite facing holes. Then finish the whole process with a bow.