You're almost there: all you need to do is shifting the individual bytes into position before OR
-ing them together.
int test2 = (value1 << 24) | (value2 << 16) | (value3 << 8) | value4;
Don't forget to make your 68
s hex for the desired output of 0xFF686868
int value2 = 0x68; // Add 0x to all three of the 68s