I agree, it is getting repetitive. Have we got it? Are the lessons not learned?
Leviticus is one part of the Bible where not only that the text recounts things that are repeating themselves, even the text reads like another repeat, but different chapter and verses, and even in a different book. Following “Next is final” (Leviticus 8:7) is “Yes, no or ?” (8:8-9), which is followed by “The cot, the donkey, the star” (8:10). In Leviticus 8:11-12, we have actions and words that are not entirely new, part or most of the details in the verses have occured in previous verses. Before we turn away, we need to focus on the intent here.
Reading a text and deducing additional information not recorded in the text is a dangerous exercise. We must do this, if it becomes necessary, at the miminum in harmony with the immediate verses or context of the passage, taking into consideration the wider societal factors. 
In Leviticus 8:11-12, there is not stated “reasons” or intent for the action. But the wider context is about worship.
A step further, the theme of worship is about a certain set of actions and objects associated with some meaning. We can easily read this as “dedication”, or “anointing”, or “calling” of someone to a task or a role. In this case, it is a kind of “holy office”. But that is because we know the context. If we are new to the passage and / or lack appreciation of the general context of Leviticus, we might say they are getting themselves ready for something special. Not only that, there is clearly one person performing action on others, they don’t perform those actions to each other, and the first person did not receive those actions from those he first did. This is not meant to be arising some potentially confusion details, but clearly there is a set of actions, and use of objects, that is one person doing it for the others.
even the text reads like another repeat
One of the key things here is about intent. The person doing the actions with the objects on the others – what is the intent? Sometimes, it can be useful to double check our response by asking what is “not” the intent? For example, trying out new garment is not an intent here. We can read that it is Moses who did the actions on others. Moses did what he was commanded. He did them as instructed. Aaron was the one mentioned here who received the action. There were various objects: some used, some placed on Aaron.
What is our intent as we approach worship?
In the last trip to church, just before setting out, I consciously recounted to myself that this was the first time I wore the new pair of shoes to this church. It’s a minor thing, but I was conscious I was coming to the house of the Lord for collective worship, different from being with God on an individual basis. There was no particular “intent” with the pair of shoes, but I was aware that I ought to be conscious of my intent.
As it turned out, there was something that would have caused me anxiety just before setting out, but my intent had already prepared me not to be distracted by misplacing that item. Secondly, arriving in church premises, two items were missing. Again, they did not distract me in preparing myself for collective worship of God, especially that I was actively setting up various equipment for use in the worship service. Further, during the worship service, a new problem developed that had slight interuption to the service. I believe that my intent was in the right place that I responded well to fixing the problem rather than being distracted by what happened, or trying to find out causes of the problem.
The words we use might be very important. The actions we do might be very crucial too. However, what is intent of our words and actions for worship?
