HOUSTON—Some early voters are learning the hard way some of the do’s and don’ts at a polling precinct.

Sheila Brayberry was turned away when she tried to vote wearing a Donald Trump t-shirt.

"I purchased it a couple of weeks ago and thought it would be fantastic to wear around town,” said Brayberry."They just weren't having it. I just don't understand why."

What she didn’t realize at the time was that political t-shirts are not allowed inside polling places.

The Harris County Clerk said the shirts are a form of campaigning which is prohibited within 100 feet of a polling location.

Singer Justin Timberlake posted a selfie on the internet showing him casting a ballot on Tuesday.

Selfies in the ballot box are also prohibited.

"You cannot do that,” said Harris County Clerk Stan Stanart."It might be somebody requiring you to show how you're voting for the purposes of being paid. Show it to your boss. Intimidation."

But issues arise at polling precincts all the time. Stanart said there is always staff on hand to voice a complaint to.

"Put your hand up and get the attention of one of the clerks or one of the judges,” said Stanart.

Brayberry got to cast a ballot after making some last minute changes to her wardrobe.

"So I went into the bathroom and flipped my shirt inside and out and went in there and voted,” said Brayberry.

Election officials said one of the reasons behind the confusion is that there are a lot of first time voters who’ve never participated in a process like this before.