There comes a time where in certain situations, although we want to put across our point, we are either unable to do so or restrain ourselves. We want to say no, we want to say our bit, but we hold ourselves back. It is in these situations where being assertive can help us in getting our point across without being aggressive or passive. 

Cognitively, to be assertive implies a lack of anxious thoughts in light of stress. Behaviourally, assertiveness is all about asking for what you want in a manner that respects others. Assertive people don't shy away from defending their points of view or goals, or from try to influence others. In terms of affect, assertiveness means reacting to positive and negative emotions without aggression or resorting to passivity – Psychology Today.

Being assertive is an interpersonal skill, it implies that you express yourself and your opinions effectively and at the same time respect the opinions and beliefs of others.

Being assertive is starkly different from being passive or aggressive. In the Passive Style, all the world is allowed on stage but for you – your role is to be the audience and supporter for everyone else. In the Aggressive Style, you're allowed on stage but you spend most of your time shoving the others off, like in a lifelong sumo match. With the Assertive Style, everyone is welcome onstage. You are entitled to be a full person, including your uniqueness, and so are others – Randy Paterson, Ph.D Clinical Psychologist.

LEARNING TO BE ASSERTIVE:
  1. Recognise Your Value: The initial step on the path of becoming assertive is to recognise your value and understand your own worth. Coming to terms with the fact that you are also an individual who has their own beliefs and opinions also helps. Valuing yourself and whatever you have to say is important, when you give yourself the power to have your own say and the confidence to go through with it, people understand that your word is essential and they learn to take you seriously.

  2. Know Your Rights: Although it may be difficult for you to believe, but you can say NO!. Whether the relationship is personal or professional, we definitely do have the right to say no. Every person has certain rights that they can exercise whenever required and by saying no you are just implementing your basic right. Learning and practicing to say no is key. You also do not need to justify your opinions and beliefs all the time, if you continue to justify your actions it in turn will make you feel guilty which will turn into a vicious cycle.

  3. Know Your Boundaries: Being assertive does not mean that you become aggressive or passive when responding to others or voicing your opinions. It is of utmost importance that we learn to keep our emotions in check and keep the aggression at bay. Being assertive does not mean that one has to be aggressive to make themselves heard, aggression in turn can make matters worse. One of the fundamentals of assertiveness is respecting your opinions while respecting the opinions of others as well, even if you are right, the manner in which you articulate things is crucial, so know your boundaries and in the drive of being assertive do not hurt others or their value systems.

  4. Express Your Needs and Feelings: When one tends to not communicate their feelings and needs whenever it is required to do so, it can create problems for them. When one gives precedence to others needs at the cost of their own, it can feel like one is being pushed into a corner which is not a favourable situation to be in. Hence, it is crucial that you express what you feel in an effective manner, wherein you are able to get your opinions across to the other person without being either aggressive or being too passive.

  5. Use "I” Statements: It is always advisable to use "I” statements, if you use words like "you” or "you're”, it can turn into accusatory statements and can escalate into arguments. Example: "You are so inconsiderate”; "You don't know how much work I had to get done today”; "Why are you asking me to go out when I'm so exhausted?”. Instead of the aforementioned statements you can say, "I am exhausted today, I understand you want to go out, but I'm too tired, isn't it better if we go out tomorrow”.

  6. Take Responsibility for Your Own Actions: Being assertive comes with certain responsibilities. When one is trying or learning to be assertive it is essential to understand that when one stands up for themselves, they must also learn to take responsibility for whatever it is that they may say or do. Being assertive can also cause certain conflicts or rub people off in the wrong way, so especially in these situations when one takes responsibility for oneself is important.

  7. Conflict Resolution: Choosing to be assertive can also come at a price. When you choose to be assertive and state your views and opinions, it’s not necessary that others may be in full agreement to what you have to say. Conflicts and differences in opinions can arise and it is the need of the hour to try and resolve these conflicts in the most effective way as possible.

  8. Make Sure You Know What You Want: In order to be assertive, one needs to be sure of what they want. Not being sure about what you want or being indecisive can prove to be a hindrance while trying to be assertive as it can confuse other people.

  9. Listen and Communicate: While trying to be assertive, it is important that one also learns to listen and communicate effectively. Assertiveness is not just about putting forth your point, it is also about listening attentively to and bringing into consideration what the other person has to say as well. Communicating effectively with the other individual is key.

  10. Say No to Guilt: Assertiveness requires one to be sure of what they say, be confident in saying whatever it is they want to say or do and putting one’s need above others whenever needed. For certain people doing these things can be quite daunting and induce a feeling of guilt within them. It is important to understand that when trying to be assertive one needs to speak for themselves, stand up to others and acknowledge their own needs and not feel guilty about it.
"When we first begin to take power more directly, after long having kept our relationship underground, it is natural that we experience anxiety, even guilt, at putting ourselves first. These feelings let us know we are taking action; they do not need to stop us” – Maureen Brady.