Entering Masjid al-Haram
Some people make a big fuss of entering Masjid al Haram through the ‘The Salaam Gate’ because the Messenger of Allah ﷺ entered through this gate. The Messenger of Allah ﷺ only entered through this gate because it was closest to him, so the sunnah is actually to enter the Masjid from the closest gate to you. The gates closest to you carry the same reward as entering through ‘The Salaam Gate’.
Masjid Al Haram is the biggest and busiest mosque in the world. If you have other people with you make a plan and discuss it beforehand. You should set a meeting point where you all plan to meet and regroup if anyone gets lost. Make sure the meeting point is a place which everyone knows and everyone knows how long to wait there for everyone.
This is just incase mobile phone connectivity fails and you don't have the ability to contact/communicate with one another remotely.
For example “If we get lost during Tawaaf, before doing safa marwa, let’s meet under this sign which reads ‘Ajyad this way’” Or “We will not stop if we lose anyone, when you have completed your Umrah and halaq, meet in the 3rd floor food court in the Clock Tower”
As you enter Masjid Al Haram then make the du'a of entering a mosque which is:
أَعوذُ باللهِ العَظيـم وَبِوَجْهِـهِ الكَرِيـم وَسُلْطـانِه القَديـم مِنَ الشّيْـطانِ الرَّجـيم،[ بِسْـمِ الله، وَالصَّلاةُ وَالسَّلامُ عَلى رَسولِ الله]، اللّهُـمَّ افْتَـحْ لي أَبْوابَ رَحْمَتـِك
As you approach the Kaaba you will stop reciting the Talbiyah. Upon seeing the Kaaba there is no specific du'a, however if you feel an increase in your imaan, then there is no harm in making your own du'a.
Taking a break
If you feel tired during any part of your Umrah, there is no harm in taking a break, going to the toilet or having a drink of water. When you return from your break, simply pick up where you left off. With tawaaf remember to do wudhu when you come back.