Makrooh acts of Ihram are some things:
1- Wearing black Ihram clothing and it is precaution to renounce that and wearing white Ihram clothing is better.
2- Sleeping in yellow bedding and pillow for Muhrim.
3- Wearing impure clothing of Ihram and if clothing become impure during Ihram, it is better not to wash them in the state of Ihram, but it is possible to change that clothing.
4- Wearing striped clothing of Ihram.
5- Using henna before Ihram in the way that its effects remain until Ihram.
6- It is better for Muhrim not to use washcloth or like that on the body.
7- It is precaution to say Labbayk answering someone who is calling Muhrim.