Dr Al Neyadi will depart the International Space Station on Saturday, bringing his six-month science mission to an end.
He will return to Earth with three of his colleagues on board a SpaceX Dragon capsule.
A video posted on Dr Al Neyadi's social media channels on Wednesday showed him putting on the spacesuit to check it fit.
"I tested the SpaceX suit to make sure it didn't need any adjustments after spending so much time in space," he said.
"We will wear this suit again in a few days, God willing, when we return via the Dragon vehicle."
Dr Al Neyadi will wear the suit during departure from the ISS, entry into Earth's atmosphere and splashdown. He and his colleagues can take their suits off once the capsule is in a stable flight path after undocking from the station.
Nasa tracking Hurricane Idalia in Florida
Meanwhile, Nasa has been monitoring Hurricane Idalia, which has made landfall in Florida.
The US space agency is assessing what effect the storm could have on the recovery of the capsule, called Endeavour, once it has splashed down off the coast of Florida.
Idalia has swept into Georgia after hitting in Florida on Wednesday, leaving hundreds of thousands without power.
"Joint teams are monitoring weather forecasts across seven potential splashdown sites off the coast of Florida and any impacts Hurricane Idalia may have on recovery operations," Nasa said on Wednesday.
Dr Al Neyadi and his colleagues will spend their final days on board the ISS handing over their tasks to a new crew that arrived at the station last week.
Dr Al Neyadi's crew are also carrying out checks on the capsule to ensure they will have a safe flight home.
"The Earth-bound foursome has been handing over its responsibilities to the newly arrived crew while preparing for the return to Earth’s gravity environment," Nasa said.
"The four crewmates this week have been packing Endeavour, reviewing deorbit and splashdown procedures and talking to Nasa and SpaceX ground support personnel."
Nasa said that it would release the timetable of the crew's return trip once it was available.