Trust is built on that foundation of reliability in any relationship. Following through by being consistent with your words and actions create that comfort factor where the other person knows that you are reliable, and that you do care about their feelings and needs.
There is a great deal of security establishing the connection from time to time as when people know others can help or support them, they tend to be stick together quite tightly.
It does not entail being perfect, it involves honoring your commitments and being honest when things have changed. If you are promised to help someone or if you promise to complete a task or an assignment, do your best to adhere to that promise.
If something unexpected comes up be honest and provide remedies. This degree of transparency respects and solidifies trust.
Consistency also comes in how you treat other people. Being consistent and considerate, despite how you feel or what you are going through outside of the relationship, is very key to ensuring the other person feels emotionally secure.
Consistency paints the other person a mental picture of your bonding, but fluctuating behaviour makes us doubt or get confused about your intentions and commitment.
Keep track of your obligations via reminders or calendars so you can always follow through on your commitments. Being on time and remembering even the smallest details of someone else life will make a big difference about how someone will perceived your reliability.