Okay today is an easy workout and all you need is some kind of stick... a broom will work fine.
Following are 3 exercises for obliques with a broom (or any other stick long enough)
1. Sit on the floor and lean back until your torso is at a 45% angle with the floor.
2. Hold the broom across the back of your shoulders. (The same place the bar would be if you were going to squat with it.) Your hands should be at each end of the broom handle so that they are outstretched.
3. Twist from side to side touching the end of the broom handle on each side of you. The handle is going to touch behind you. Make sure you are twisting your torso not just dropping your shoulders from side to side.
Next you will do the same thing but instead of leaning back to a 45% angle you can sit on a chair straight up and twist with the bar still resting across you shoulders. You want to make sure you twist only your torso and not your pelvis. Keep you head straight and focus on using your obliques to turn.
And the 3rd exercise is another variation of the same. With the broom resting across your back/shoulders you are going to stand with feet shoulder width apart and bend at your waist as far as you can, which will be 90 degress for some people. Then you will twist all the way to one side and hold for 2 seconds then twist to the other. Remember to keep your pelvis from moving.
I know reading these it seems like it wouldn't be a good workout but trust me it is.. you will feel it.