Yeah, i'll list every command you need to do to build from source.
OPEN TERMINAL
git clone https://github.com/iridiumdev/iridium.git
cd iridium
sudo apt-get install libboost-all-dev
sudo apt-get install build-essential
sudo apt-get install make
make -j 2 -i

Once it is done compiling, if something didn't go wrong, go to iridium/build/release/src and you should see the files iridiumd and simplewallet in there.

Open a terminal in this directory and type:
./iridiumd
Open another terminal and type:
./simplewallet


I also noticed someone is trying to send lots of transactions without adding the minimum fee, since all transactions are working now, you need to update to the latest iridiumd file on github, and it should solve the issue. Thanks