Narrative:

I had not flown since march of this year; due to all the covid virus going on nationwide. A friend asked me to reposition a newly acquired aircraft from ZZZ1 to ZZZ2. Weather was currently and forecast to be VFR the entire route; but I filed it IFR to get myself back to speed on instruments; which I thought I did a good job of this trip. My first stop was ZZZ for fuel. Had gotten dark by then; about xa:30pm local time. [My] clearance departing was to fly the 'zzzzz X to zzzzz [intersection]; then on course'...as I heard it and understood. My next intersection; which I had filed to from the airport was ZZZZZ1 intersection. So that is where I was attempting to navigate to after I passed zzzzz. So ATC calls me on radio and says I was supposed to fly on to ZZZZZ2 intersection and then do the 15 mile arc around to ZZZZZ1. (This was not what I understood in the departure clearance.) they vectored me on towards ZZZZZ1; and I continued.I should have asked for vectors before departing the airport; instead of the SID. The GPS in the airplane was not quick/easy to alter any data; but I was doing ok with it enroute.

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Original NASA ASRS Text

Title: GA pilot reported a track deviation during departure and cited clearance confusion as a contributing factor.

Narrative: I had not flown since March of this year; due to all the COVID virus going on nationwide. A friend asked me to reposition a newly acquired aircraft from ZZZ1 to ZZZ2. Weather was currently and forecast to be VFR the entire route; but I filed it IFR to get myself back to speed on instruments; which I thought I did a good job of this trip. My first stop was ZZZ for fuel. Had gotten dark by then; about XA:30pm local time. [My] clearance departing was to fly the 'ZZZZZ X to ZZZZZ [Intersection]; then on course'...as I heard it and understood. My next intersection; which I had filed to from the airport was ZZZZZ1 Intersection. So that is where I was attempting to navigate to after I passed ZZZZZ. So ATC calls me on radio and says I was supposed to fly on to ZZZZZ2 Intersection and then do the 15 mile arc around to ZZZZZ1. (This was not what I understood in the departure clearance.) They vectored me on towards ZZZZZ1; and I continued.I should have asked for vectors before departing the airport; instead of the SID. The GPS in the airplane was not quick/easy to alter any data; but I was doing OK with it enroute.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.