what a interesting sentence. 2 keys. 1. 2rd tone that you want to emphasize. 2. 3rd tone the last word, not only of the sentence but the rhythm. e.g. 我想你。你, as the last word, is always the 3rd tone so 想 before a 3rd tone word is always the 2nd tone. and the 1st one, 我, when you want to emphasize it, that is I,not anybody else, miss you. it shoud be the 2nd tone and if you want to emphasize 想, you can make 我 the 3rd tone. the 3rd-tone word at the end is ALWAYS the 3rd tone even if in a ? sentence. now, pay attention to the rhythm. the rhythm of a sentence depends on what you want to emphasize. e.g. if you want to emphasize 你, you should make a 我想/你也得..... rhyhm and if you want to emphasize 也, it should be 我想你/也得..... in fact, there is no rule of 3rd ->2nd tone, just because several 3rd-tone words put together sound like the 2nd. remember the last one never changes, the others as you like.

2 2 3 2 2 3 3 2 3 2 我想你也得给李老板点儿面子 How did u find this hard sentence? It's interesting. But in my opinion, tones are not that important for foreigners. We can understand u even u r not speaking correct tones.

when there are double-3,the former 3 may sound like 2(you are actually pronouncing 3) ex. 老虎 lao3 hu3 sounds lao2 hu3