For skinny rims mount one side of the tire. Now put the valve in and the inner inside the tire, carefully isn't folding or twisting. Now mount the other side of the tire, starting from the valve. Push the valve in to give some room to the tire beads.
You can also put a strap or just put your weight in the tire at the valve so it doesn't jump out of the rims during inflation
For skinny rims mount one side of the tire. Now put the valve in and the inner inside the tire, carefully isn't folding or twisting. Now mount the other side of the tire, starting from the valve. Push the valve in to give some room to the tire beads.
You can also put a strap or just put your weight in the tire at the valve so it doesn't jump out of the rims during inflation