Tai chi and baguazhang balance yielding/making space with vigorous counter-attacks.
Your aim is not to take turns, or fight.
Your aim is to finish the attacker off swiftly and decisively.

This means being present, being alert, and taking advantage of every opportunity.
You cannot space out.

A good time to train your countering skills is when 'playing the attacker'.
If you are convincing, the defender is positively challenged.
You train your attacking and counter-attacking skills simultaneously... every time you play the attacker.
Focus.

The 13th principle of the 13 postures is called 'central equilibrium'.
One aspect of central equilibrium is the notion of core stability.
Stabilising the centre does not involve any form of tension.
It is about awareness, rather than doing.

By allowing the pelvis to relax naturally and being conscious of the body in motion; a tai chi student can develop 'core stability'.
Core stability means that the pelvis feels to stay where it is throughout your practice, rather than tilt or twist.

Use the body to deliver force, not the hands.
If you can de-stabilise your opponent by taking their balance, you can employ force without receiving resistance.
Keeping your hands within the range of your feet will help in this endeavour.