While reading up on the Kineticist, I noticed it never expressly says what modifier you add to attack rolls with your kinetic blast. So, what are all the modifiers you add to a kinetic blasts attack roll?
Kinetic blasts are described as ranged attacks, and unless otherwise noted you add your Dexterity modifier to ranged attack rolls
From the Kineticist page :
Physical blasts are ranged attacks that deal an amount of damage equal to 1d6+1 + the kineticist's Constitution modifier, increasing by 1d6+1 for every 2 kineticist levels beyond 1st. Spell resistance doesn't apply against physical blasts. Energy blasts are ranged touch attacks that deal an amount of damage equal to 1d6 + 1/2 the kineticist's Constitution modifier, increasing by 1d6 for every 2 kineticist levels beyond 1st.
From the general combat rules :
Your attack bonus with a melee weapon is : Base attack bonus + Strength modifier + size modifier
Your attack bonus with a ranged weapon is : Base attack bonus + Dexterity modifier + size modifier + range penalty
Some attacks completely disregard armor, including shields and natural armor—the aggressor need only touch a foe for such an attack to take full effect. In these cases, the attacker makes a touch attack roll (either ranged or melee).
So you just use your Dexterity modifier for attack rolls.