Rather than having an abstract idea about these 5 elements and in particular about the Akasha element you can also have a more direct and a "related to your own physical body" kind of concept for each of them .
Such expositions of ideas are found in the Yoga Tattva Upanishad (which is associated with the Krishna YajurVeda). Here Lord Vishnu is doing all the explanations:
83(b). There are the five elements: Prithvi, Apas, Agni, Vayu and
84-87(a). To the body of the five elements, there is the fivefold
Dharana. From the feet to the knees is said to be the region of
Prithvi, is four-sided in shape, is yellow in colour and has the Varna
(or letter) ‘La’. Carrying the breath with the letter ‘La’ along the
region of earth (viz., from the foot to the knees) and contemplating
upon Brahma with four faces and four mouths and of a golden colour,
one should perform Dharana there for a period of two hours. He then
attains mastery over the earth. Death does not trouble him, since he
has obtained mastery over the earth element.
87(b)-90. The region of Apas is said to extend from the knees to the
anus. Apas is semi-lunar in shape and white in colour and has ‘Va’ for
its Bija (seed) letter. Carrying up the breath with the letter ‘Va’
along the regions of Apas, he should contemplate on the God Narayana....
91. From the anus to the heart is said to be the region of Agni. Agni is triangular in shape, of red colour and has the letter ‘Ra’ for its
92-93(a). Raising the breath made resplendent through the
letter ‘Ra’ along the region of fire, he should contemplate on Rudra,
who has three eyes, who grants all wishes, ....
94(b)-96. From the heart to the middle of the eyebrows is said to the
region of Vayu. Vayu is hexangular in shape, black in colour and
shines with the letter 'Ya’. Carrying the breath along the region of
Vayu, he should contemplate on Ishvara, the Omniscient.....
From the centre of the eyebrows to the top of the head is said to be
the region of Akasa, is circular in the shape, smoky in colour and
shining with letter ‘Ha’.
98(b)-101(a). Raising the breath along the region of Akasa, he should
contemplate on Sadashiva in the following manner, as producing
happiness, as of the shape of Bindu, as the great Deva, as having the
shape of Akasa, as shining like pure crystal, as wearing the rising
crescent of moon on his head, as having five faces, ten hands and
three eyes, as being of a pleased countenance, as armed with all
weapons, as adorned with all ornaments, as having Uma (the goddess) in
one-half of his body, as ready to grant favours and as the cause of
all the causes.
So,the region from between the centre of the eyebrows to the top of your head is the region of Akasha.Thus,Akasha is not anymore abstract but quite tangible now.
The Supreme Being Sadashiva along with his Shakti(Uma) reside there in the form of Ardhanareeswara.