How can I make McDonald's type French Fries
What you want is Kenji Lopez-Alt. Here.

Summary:  


Cut fries 1/4 inch thick to maximize crispiness  
Blanch fries with a little vinegar in the water
The vinegar preserves the potatoes' pectin and keeps them from disintegrating in the water
Briefly fry
Freeze the fries
This opens up their internal structure and allows more crispification
Before serving, fry for the last time


Another advantage of doing fries this way is that the blanching, pre-frying, and freezing can be done in large batches in advance.