The following chronology follows Rashi’s understanding of the verses.
1 Sivan - Bnei Yisrael arrive at Har Sinai (Shemos 19:1 - Yisro)
2 Sivan - Moshe is told that we are to be a Mamleches Kohanim V'goy Kadosh; the people answer Na'aseh (Rashi to 19:3 - Yisro)
3 Sivan - Moshe is instructed to prepare the people and Har Sinai for Matan Torah (Rashi to 19:8 - Yisro)
4 Sivan - Moshe makes a Bris with Bnei Yisrael and writes a Torah scroll; the people answer Na'aseh V'Nishmah (Rashi to 24:1 - Mishpatim)
5 Sivan - No information is given about the events of this day. Presumably the people continued preparing for Matan Torah
6 Sivan - HaShem held the mountain over Klal Yisrael (Rashi to 19:16 - Yisro)
6 or 7 Sivan - Matan Torah (Rashi to 19:15 - Yisro)
7 or 8 Sivan - Moshe is instructed to go up Har Sinai for 40 days (Rashi to 24:12 - Mishpatim)
---40 days (Presumably the laws of 20:20-23:33 - Yisro and Mishpatim - were given now)---
17 Tammuz - Eigel HaZahav (Rashi to 32:1 - Ki Sisa)
---40 days (34:28 - Ki Sisa; the laws of 25:1-31:17, Terumah-Ki Sisa, were given during this period - Rashi to 31:18)---
10 Tishrei - Moshe descends (34:29 - Ki Sisa)
11 Tishrei - Yisro reprimands Moshe regarding his judging methods (Rashi to 18:13 - Yisro)
Next several months - Mishkan was built (Vayakhel-Pekudei) and dedicated (first several parshios of Vayikra and Bamidbar)
As you can see from the above, the events of Yisro, Mishpatim, Terumah, Tetzaveh, and Ki Sisa are all mixed up, with the normal order being resumed with Vayakhel. Why? Granted that the Torah is not necessarily written in order (Pesachim 6a, cited by Rashi to Shemos 31:18), there's always a reason why everything is where it is. So why are these events not written in order?
Rashi in his comments throughout Rishon of Yisro seems to indicate that he personally holds that Yisro came before Matan Torah, while later addressing the other opinion as an aside. So this question will not seek an answer addressing that particular piece since it is in place according to him.