Your question shows your desire to come close to Allah and gain His goodly pleasure. I pray to Allah to help you achieve your goal.

Now coming to your question, let me sum up some of the things you should focus on in order to prepare ourselves for meeting Allah:

1. It is necessary to make sincere repentance, and ask forgiveness of Allah for our transgressions and violations. There are two types of transgressions:  1. Those that concern violations of the rights of Allah; 2. Those that are related to violations of the rights of humans. In the case of the former, it is necessary to fulfill the following conditions for repentance: 1. Refraining from those sins immediately; 2. Feeling sincere remorse for committing them; 3. Resolving in one's mind never to do them again; 4. Doing whatever virtuous deeds one can in order to expiate for the past sins.
2. As for the violations involving the rights of humans, we need to seek forgiveness of them; if we have robbed someone we need to return the things we have taken; if we cannot do so, then we need to give the amount in charity and thus get rid of the unlawful earnings. If, on the other hand, we have hurt someone or injured their feelings, etc., we need to ask forgiveness of them; if that is impossible,   we need to redeem ourselves by offering charities on their behalf or praying for them.
3. Having done the repentance, we need to be diligent in our observance of our religious duties.
4. We should practice dhikr as much as possible. Dhikr can take many forms: reading and listening to the Qur'an, offering supplications, or meditating on the words of praise and glorification of Allah or meditating on His beautiful names, etc. it would be most beneficial for you to get a copy of Invocation of God by Ibn al-Qayyim al-Jawziyyah; study it and practice it.
5. Occupy our time and energies in doing righteous works for the pleasure of Allah.
6. Finally treat everyone you come across with mercy and kindness. The Prophet (peace be upon him), said, "Show mercy to those on earth: the One in heaven will be merciful to you."