On Survivor one tribe gets immunity, the losing tribe must vote off one of their own.

In The Amazing Race, the last person to cross the finish line gets eliminated.

On The Apprentice, Donald fires either the losing project manager or one of their 2 scapegoats.

How do the other reality shows eliminate people? I am trying to plan a game to play with my friends with stupid little challenges, that end up eliminating someone each round. I want to make each challenge like a different reality show, but I need ideas.

Can anyone give me some help? How does Big Brother do it? Or The Mole? Or any of the other shows?

On The Mole it's the person who has the lowest score on a test they take asking questions about who they think the Mole is.

On the dating shows like the Bachelor, Bachelorette, Average Joe, For Love or Money, Who Want to Marry My Dad, Joe Millionaire, etc... the guy or gal decide who to eliminate at the end of each episode.

On Big Brother one contestant wins a weekly competition to become 'head of household'. As HoH, that person gets to "nominate" two other housemates for eviction. From those two, the other housemates vote on who to evict.

The best was Paradise Hotel and how obvious it was that it was fixed.

I thought people then called in to vote someone off... have they changed it since season 2?

Yes

Boot Camp - Each episode two are discharged. Squad votes to discharge one member. Discharged member then picks the second member to be discharged.

Murder in Small Town X - The person appointed 'lifeguard' picks one player to face elimination. The other players vote for the second player. Each player picks a site to investigate randomly. One wil return, one will be "killed".

Combat Missions - Losing team must vote off a squad member.

Last Comic Standing - Players vote for a player to face elimination. That player then picks a player among those who voted for him/her. They face off in a comic showdown at a comedy club, and the club audience votes for their favorite. The second place finisher is eliminated.

On Star Search, there are 3 winners from previous Star Searches in each category willing to take on challengers. I think they call it something like the inner circle.

Each week, 2 new challengers battle each other (singing, dancing). The challenger with the most votes from the 3 judges then gets to challenge one of the 3 previous winners to perform to retain their spot in the inner circle, and if the new challenger's score is higher than the previous winner who got challenged, then the challenger takes their spot in the inner circle of 3. Otherwise, they go home.