What happens next?

How to be more aggressive
Be assertive in your posture.
You want to appear in control, poised, and confident without looking awkward or uncomfortable.
Approach someone directly, rather than from the side of behind.

(a). This allows for complete eye contact and trust. If you are sitting on the floor or even leaning against a wall, remember to keep your shoulders back and your stance neutral.
(b). Lean forward slightly to give someone the distance needed to make the first move. By demonstrating this you will get the person's attention to you.
(c). Maintain enough distance so you can hear the person but are not in their face. Relax (do not slouch or hunch) your shoulders and spread your feet shoulder-width apart so your body weight is balanced evenly on both legs.
(d). Stand tall, or walk with an awkward position, and avoid running up to them. Stand firm and walk with confidence, with your legs shoulder width apart.
(c).