Do not wear make-up or jewellery. Do not commit adultery. Rehatnama Bhai Daya Singh Jee
Historic fact:
When Sikh woman were captured by the Evil Mughal Government, they pierced her nose and put a ring on her as a sign of slavery (just like people do when they own a cow etc). They also put all types of noise making jewellery like bell ear rings etc so that when they made them dance, the noise made would add to their enticement. Our women used to be forced to wear this crap to satisfy the enemies’ evil desires, but now our women become slaves themselves.
She becomes His soul-bride forever, with the Word of the Shabad in her mind; she makes the Fear of God and the Love of God her ornaments and decorations. Ang 787 Sri Guru Granth Sahib Ji
Discarding worldly adornments, she meets her Husband Lord, and she celebrates joyfully with Him. She is adorned forever with the Name in her mind, and she does not have even an iota of filth. Ang 642 Sri Guru Granth Sahib Ji
The hair, moustache and beard are created within God's order. How can those who violate their natural form by cutting their hair ever be accepted by the Lord? Rehatnama Bhai Desa Singh
A Sikh must be distinguished by a turban, a fine flowing beard, and an uncut kes. He must never use a razor or remove his beard. Rehatnama Bhai Desa Singh
However Some Sikhs have to tie up their beards in factory jobs etc for their own safety (Which is understandable).
On each and every hair, the Lord abides. Ang 344 Sri Guru Granth Sahib Ji
Comb your hair twice daily and re-tie your turban each time your wear it. Rehatnama Bhai Nand Laal Jee
He who as a Sikh places a hat on their head; will be reborn seven times as a leper. Thankhaanama Bhai Nand Laal Jee
So that hat type starch things (so called turban) that people wear are of no use as they are the same as a hat. However to disguise themselves some Sikh warriors have worn hats etc for survival, even Sri Guru gobind Singh Ji dressed as a Muslim peer to escape from enemy hands to safety (So a hat as a disguise seems to be understandable).
Worship the Divine, Supreme Soul, with the intuitive peace and poise of the Guru. If the individual soul has faith in the Supreme Soul, then it shall obtain realization within its own home. The soul becomes steady, and does not waver, by the natural inclination of the Guru's Loving Will. Ang 87 Sri Guru Granth Sahib Ji
Lion of the Guru In natural form