What are the means of remembering adhkaar and not forgetting them?

Firstly: 

Remembrance
of Allaah (dhikr) is one of the greatest acts of worship and best acts of
obedience. It is a means of rising in status. Allaah has not set any limit
for remembrance of Him, rather He has enjoined remembering Him a great deal.
Allaah says (interpretation of the meaning): 

“and
remember Allaah much, that you may be successful”

[al-Jumu’ah 62:10] 

“Verily,
the Muslims (those who submit to Allaah in Islam) men and women, the
believers men and women (who believe in Islamic Monotheism), the men and the
women who are obedient (to Allaah), the men and women who are truthful (in
their speech and deeds), the men and the women who are patient (in
performing all the duties which Allaah has ordered and in abstaining from
all that Allaah has forbidden), the men and the women who are humble (before
their Lord ___Allaah), the men and the women who give Sadaqaat (i.e. Zakaah
and alms), the men and the women who observe Sawm (fast) (the obligatory
fasting during the month of Ramadân, and the optional Nawafil fasting), the
men and the women who guard their chastity (from illegal sexual acts) and
the men and the women who remember Allaah much with their hearts and
tongues. Allaah has prepared for them forgiveness and a great reward (i.e.
Paradise)”

[al-Ahzaab 33:35] 

In the
Qur’aan, Allaah does not enjoin doing any act of worship a great deal,
except remembrance of Allaah (dhikr). In the remembrance of Allaah hearts
find rest.  

“Those
who believed (in the Oneness of Allaah — Islamic Monotheism), and whose
hearts find rest in the remembrance of Allaah verily, in the remembrance of
Allaah do hearts find rest”

[al-Ra’d
13:28] 

In order to
find out the means that help one to remember the adhkaar for the morning and
evening, it is essential, first of all, to find out the causes of forgetting
and neglecting them, then deal with these causes. 

1.    
Carelessness in memorizing
these adhkaar and relying on booklets to recite them.

2.    
Being distracted by worldly
matters at the expense of time for the morning and evening adhkaar.

3.    
Not knowing the worldly
benefits of these adhkaar, such as protection for the one who recites them,
opening the door to provision and warding off evil for the one who recites
them, and the benefits in the Hereafter, such as a reward equivalent to that
of freeing a slave, making the Balance weigh heavily, and earning the good
pleasure of Allaah, may He be exalted

4.    
Committing many sins, which
affects the person’s heart and prevents him from remembering Allaah.

5.    
Ignorance of the time for the
morning and evening adhkaar, so he thinks that the time for the morning
adhkaar ends with Fajr prayer, for example, and the time for the evening
adhkaar ends with ‘Asr prayer, for example. In fact the time for the morning
adhkaar lasts until after sunrise, and the time for the evening adhkaar
lasts until after sunset. For more information please see question no.
22765. 

The way to
deal with these causes is as follows: 

1.    
Try to memorize most of these
adhkaar so that you will be able to recite them in the car or on the way to
work or school, without needing the book.

2.    
Pondering the meanings of these
adhkaar that are prescribed in Islam, because many people recite these
adhkaar without understanding the meanings, which weakens or cancels out
their effect on reforming the heart.

3.    
Setting aside a specific time
in the morning and evening for reciting these adhkaar and sticking to it,
and ignoring everything that may distract you from that.

4.    
Do not delay reciting these
adhkaar when you remember to do so, because putting off such things may lead
to forgetting them.

5.    
Finding out what has been
narrated in the Qur’aan and Sunnah of the great rewards in this world and in
the Hereafter for the one who remembers Allaah. Undoubtedly this will
encourage you to remember them and not neglect them.

6.    
Keep away from sins so that
your heart will remain sound and sincere, longing to remember Allaah.

7.    
Strive to take a gradual
approach in learning these adhkaar. Do not set yourself a program of
reciting everything that is narrated in the book of adhkaar, so that you
will not make things too difficult for yourself, which may lead you to give
up. Rather you should recite a small portion so that you can taste the
sweetness of dhikr, and increase it gradually.

8.    
Read the biographies of
worshippers who strove hard in the remembrance of Allaah, so that it will
encourage you to follow their example and strive as they strove.

9.    
Urge your wife, children and
family to remind one another of these adhkaar, for the believer gains great
support through his brothers.

10.
Seek righteous friends who will
help you to remember Allaah and remind you of adhkaar and acts of worship. 

Thirdly: 

Book which
speak of these adhkaar and their virtues include the following: 

1.    
al-Adhkaar
by al-Nawawi

2.    
al-Kalim al-Tayyib
by Ibn Taymiyah, annoted by al-Albaani.

3.    
al-Waabil al-Sayyib
by Ibn Qayyim al-Jawziyyah

4.    
Tuhfat al-Dhaakireen
by al-Shawkaani

5.    
Tuhfat al-Akhyaar
by Shaykh Ibn Baaz

6.    
Fiqh al-Ad’iyah wa’l-Adhkaar
by Shaykh ‘Abd al-Razzaaq ibn ‘Abd al-Muhsin al-‘Abbaad

7.    
al-Ma’thooraat min
al-Adhkaar wa’l-Da’waat by Shaykh
‘Abd-Allaah al-Qusayr

8.    
Saheeh al-Adhkaar wa’l-Du’aa
al-Mustajaab by Shaykh Mustafa al-‘Adawi 

And Allaah
knows best.