The first two moves of Heian Yondan are all about attitude!
There are many applications for the first two moves in Heian Yondan, but in the kata, they are performed slowly, using zanshin (total awareness) and kamae (mind and body ready).
The feeling should be strong, like you are ready to fight, focus, deep breathing in and out, try not to speed up at the end of each technique, instead keep the moves constant am]nd smooth, no shuddering, jerky movements.
Each of the first two moves should take approximately 3 to 4 seconds.
Keep a good kokutsu dachi (back stance) and try and keep the wrists straight. Each arm is bent at a ninety degree angle, wrist near the forehead on one arm, with the elbow directly out from the shoulder on the other arm. Arms should make a box shape as in Heian Nidan.
Here is the full Heian Yondan Kata Tutorial.