To solve this I'm going to split the middle term.
First multiply the first and last terms:
24x^2
So find two numbers that multiply to 24x^2 and add to 11x.
This would be 3x and 8x
Rewrite the problem as
4x^2+3x+8x+6
Take the first and 3rd and 2nd and 4th terms
4x^2 and 8x
and
3x and 6
Factor by grouping
Take out a 4x for the first group to get 4x(x+2)
Take out a 3 for the 2nd group to get 3(x+2)
Rewrite as (4x+3)(x+2)
Hope this helps.