Description of Lord Shiva marriage with mother Parvati is described in many Puranas but I am writing the answer based on Shiva Mahapurana, Rudra Samhita, Parvati Khanda, Chapter 43.
Mena, the mother of Devi Parvati wanted to know that how lord Shiva looks. So, she went to see lord Shiva. Lord Shiva knows her ambitions so, he played a game with her. First he told all other Gods to go on the entrance of palace. By Lord Shiva commands all Gods went on entrance one by one including Gandharva, Vasu, Yaksha, Yama, Nirritti, Kubera, Indra, Chandra, Surya, Brihaspati, Lord Brahma and Lord Vishnu. Mena thought that Lord Shiva will be more graceful than others. But Lord Shiva shown her his umblemished and unconnected form. By seeing him, Mena felt unconscious.
इत्यवादीच्च सा मेना प्रेमनिर्भरमानसा। तावत्समागतो रुद्रोऽद्भुतोभीतिकरः प्रभुः॥४५॥
Brahma said, “When Mena spoke so lovingly, by that time, Rudra with a terrific form arrived there.
अद्भुतात्मगणास्तात! मेनागर्वापहारकाः। आत्मानं दर्शयन् मायानिर्लिप्तं निर्विकारकम्॥४६॥
O Dear one, his ganas, were also of astonishing types and could shatter the pride of Mena. Because of his illusion he displayed his umblemished and unconnected form.
तमागतमभिप्रेत्य नारद! त्वं मुने! तदा। मेनामवोचः सुप्रीत्या दर्शयंस्तं शिवापतिम्।। ४७॥
O Sage Narada, at the sight of Siva, so arriving, you lovingly pointed out to her the bridegroom Siva, and spoke to her.
अयं स शङ्करः साक्षाद्दृश्यतां सुन्दरि! त्वया। यदर्थ शिवया तप्तं तपोऽति विपिने महत्॥४८॥
Narada said, “This is Siva, O Comely
damsel, you look at him. It was for him that Parvati performed hard tapas in the forest."
इत्युक्त्वा हर्षिता मेना तं ददर्श मुदा प्रभुम्। अद्भुताकृतिमीशानमद्भुतानुगमद्भुतम्॥४९॥
Brahma Said, "At these words of Narada, Mena looked delightfully at Siva appearing in an astonishing form with his ganas.
तावदेव समायाता रुद्रसेना महाऽद्भुता। भूतप्रेतादिसंयुक्ता नानागणसमन्विता।। ५०॥
At the same time the immensely surprising army of Siva’s ganas also arrived, comprising of the ghosts, goblins and several others,
वात्यारूपधराः केचित्पताकामर्मरस्वनाः। वक्रतुण्डास्तत्र केचिद्विरूपाश्चापरे तथा। ५१॥
Some of them had the form of storm, some of them resembled the banners, creating hissing sound, some had crooked faces, while others were deformed.
करालाः शमश्रुलाः केचित् केचित्खञ्ज ह्यलोचनाः। दण्डपाशधरा: केचित् केचिन्मुद्ररपाणयः॥५२॥
Some of them looked awful with overgrown beards and moustaches. Some were lame, blind while others were holding danda
and pasa. Some of them carried clubs in their hands.
विरुद्धवाहनाः केचित्छ्रङ्गनादनिनादिनः। डमरोर्वादिनः केचित्केचिद्गोमुखवादिनः॥ ५३॥
Some rode over the Vehicles facing backwards, some of them were blowing horns,
some played on small double drums and Gomukhas.
अमुखा विमुखाः केचित्केचिह्नहुमुखा गणाः। अकरा विकराः केचित्केचिट्टहुकरा गणाः॥५४॥
Some of them had no faces at all, some of them had many faces, some of them had no hands, some had deformed hands while others had many hands.
अनेत्रा बहुनेत्राश्च विशिराः कुशिरास्तथा। अकर्णा बहुकर्णाश्च नानावेषधरा गणाः॥५५॥
Some had no eyes, some had many eyes, some were without heads, some had deformed
heads. Some had no ears, some had many ears. Some of them could take to many forms.
इत्यादि विकृताकारा अनेके प्रबला गणा:। असङ्खयातास्तथा तात! महावीरा भयङ्कराः॥५६॥
Thus the deformed type of ganas, who were immensely valorous, were beyond counting and terrible at the same time.
अङ्गुल्या दर्शयंस्त्वं तां मुने! रुद्रगणाँस्ततः। हरस्य सेवकन्यश्य हरं चापि वरानने!॥ ५७॥
O Sage, you while pointing out towards the ganas, said to Menā, “O Beautiful one, these are the ganas of Siva.”
असङ्खयातान् गणान् दृष्टा भूतप्रेतादिकान्मुने!। तत्क्षणदभवत्सा वै मेनका त्राससङ्कुला॥५८॥
O Sage, looking at the innumerable ghosts and goblins, Mena felt frightened.
तन्मध्ये शङ्करं चैव निर्गुणं गुणवत्तरम्। वृषभस्थं पञ्चवक्त्रं त्रिनेत्रं भूतिभूषितम्॥ ५९॥
कपर्दिन चन्द्रमौलि दशहस्तं कपालिनम्। व्याघ्रचर्मोत्तरीयञ्च पिनाकवरपाणिनम्॥ ६०॥
These deformed ganas were surrounding Siva from all the sides, who was seated over the virtuous Nandi, having five faces, three eyes, applying ashes over the body, having the matted locks of hair, with crescent moon over
the head, ten hands, carrying a skull, clad in tiger skin over the body, carrying the excellent bow- Pinaka.
शूलयुत विरूपाक्ष विकृताकारमाकुलम्। गजचर्म वसानं हि वीक्ष्य त्रेसे शिवाप्रसू:।।६।१।
He held a trident, was having odd eyes, ugly features utterly dishevelled hair and was untidy. He was wearing the elephant hide, looking at whom the mother of Siva was frightened.
चकितां कम्पसंयुक्तां विह्वलां विभ्रमद्धियम्। शिवोऽयमिति चाङ्गुल्या दर्शयैस्तां त्वमब्रवीः॥ ६२॥
She was taken a back, and while shaking, confused, Mena was told by you, "This is Siva," pointing out towards him.
त्वदीयं तद्वचः श्रुत्वा वाताहतलता इव। सा पपात दुप्तं भूमौ मेना दुःखभरा सती॥६३॥
Listening to your words, Mena, felt painful and fell down on earth, like the creeper shattered by the wind storm.
किमिदं विकृतं दृष्ट्रा वञ्चिताऽहं दुराग्रहे। इत्युक्त्वा मूर्च्छिता तत्र मेनका साऽभवत्क्षणात्॥ ६४॥
Then she uttered, “What is all this? I have been cheated for being too ambitious. This deformity is of what use to me?” Saying this, Menaka fell down on earth, unconsciousness.
अथ प्रयत्त्रैर्विविधैः सखीभिरुपसेविता। लेभे सञ्ज्ञां शनैमेंना गिरीश्वरप्रिया तदा। ६५॥
Her maids tried in various ways (to bring her back to consciousness) and kept on attending on her. Then slowly, the beloved of the mountains, regained consciousness.